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How do you detect Credit card type based on number?

I'm trying to figure out how to detect the type of credit card based purely on its number. Does anyone know of a definitive, reliable way to find this?

Using a regular expression. Check out this link for more information.
The details are all on Wikipedia: en.wikipedia.org/wiki/Credit_card_numbers
There's a good summary table in Wikipedia, at en.wikipedia.org/wiki/Credit_card_numbers. It's the first one to six digits that tell the type and issuer of the card.
I wouldn't use a regex other than to pull out the first numeric group, you can generally tell just from the first 4 numbers (in the US). Also before bothering to pay for clearing a charge run a Mod 10 checksum on the card number to make sure it could be legitimate. Luhn algorithm
also can anyone comment if these algorithms are good 'for all time' - or do they periodically change, like for instance the algorithm for 'calculating if a phone number is in california'

A
ArtOfWarfare

The credit/debit card number is referred to as a PAN, or Primary Account Number. The first six digits of the PAN are taken from the IIN, or Issuer Identification Number, belonging to the issuing bank (IINs were previously known as BIN — Bank Identification Numbers — so you may see references to that terminology in some documents). These six digits are subject to an international standard, ISO/IEC 7812, and can be used to determine the type of card from the number.

Unfortunately the actual ISO/IEC 7812 database is not publicly available, however, there are unofficial lists, both commercial and free, including on Wikipedia.

Anyway, to detect the type from the number, you can use a regular expression like the ones below: Credit for original expressions

Visa: ^4[0-9]{6,}$ Visa card numbers start with a 4.

MasterCard: ^5[1-5][0-9]{5,}|222[1-9][0-9]{3,}|22[3-9][0-9]{4,}|2[3-6][0-9]{5,}|27[01][0-9]{4,}|2720[0-9]{3,}$ Before 2016, MasterCard numbers start with the numbers 51 through 55, but this will only detect MasterCard credit cards; there are other cards issued using the MasterCard system that do not fall into this IIN range. In 2016, they will add numbers in the range (222100-272099).

American Express: ^3[47][0-9]{5,}$ American Express card numbers start with 34 or 37.

Diners Club: ^3(?:0[0-5]|[68][0-9])[0-9]{4,}$ Diners Club card numbers begin with 300 through 305, 36 or 38. There are Diners Club cards that begin with 5 and have 16 digits. These are a joint venture between Diners Club and MasterCard and should be processed like a MasterCard.

Discover: ^6(?:011|5[0-9]{2})[0-9]{3,}$ Discover card numbers begin with 6011 or 65.

JCB: ^(?:2131|1800|35[0-9]{3})[0-9]{3,}$ JCB cards begin with 2131, 1800 or 35.

Unfortunately, there are a number of card types processed with the MasterCard system that do not live in MasterCard’s IIN range (numbers starting 51...55); the most important case is that of Maestro cards, many of which have been issued from other banks’ IIN ranges and so are located all over the number space. As a result, it may be best to assume that any card that is not of some other type you accept must be a MasterCard.

Important: card numbers do vary in length; for instance, Visa has in the past issued cards with 13 digit PANs and cards with 16 digit PANs. Visa’s documentation currently indicates that it may issue or may have issued numbers with between 12 and 19 digits. Therefore, you should not check the length of the card number, other than to verify that it has at least 7 digits (for a complete IIN plus one check digit, which should match the value predicted by the Luhn algorithm).

One further hint: before processing a cardholder PAN, strip any whitespace and punctuation characters from the input. Why? Because it’s typically much easier to enter the digits in groups, similar to how they’re displayed on the front of an actual credit card, i.e.

4444 4444 4444 4444

is much easier to enter correctly than

4444444444444444

There’s really no benefit in chastising the user because they’ve entered characters you don't expect here.

This also implies making sure that your entry fields have room for at least 24 characters, otherwise users who enter spaces will run out of room. I’d recommend that you make the field wide enough to display 32 characters and allow up to 64; that gives plenty of headroom for expansion.

Here's an image that gives a little more insight:

UPDATE (2016): Mastercard is to implement new BIN ranges starting Ach Payment.

https://i.stack.imgur.com/Cu7PG.jpg


great example. do you have the regular expression for maestro cards?
NO, no, no. You cannot rely on the lengths of card numbers; they can change at any time. The only part of the card number you can rely on is the IIN (which used to be called a BIN) and which is a prefix of the number. Additionally, you cannot detect Mastercard cards in the manner you suggest; that will only pick up a subset of the cards that are processed via the Mastercard system (the main problem being Maestro cards, which have a variety of IIN prefixes).
@senfo You’re right, 5412 would not be a complete Mastercard number. IINs are six digits long, so a complete card number must be 7 digits (minimum) and must pass the Luhn check. There’s no need for “proof” that Mastercard numbers have anything other than 16 digits; the point is that, regardless of the situation today, in future they might issue cards with 17 or 18 digits, or for that matter some with 15. Relying on them being 16 digits long is unnecessary and creates a long-term maintenance risk.
I find it very hard to believe that some valid cards would not have a correct check digit according to the Luhn algorithm. It it used absolutely everywhere to check card numbers against simple typos and dumb fraud attempts. Instead, I have observed some quite smart people simply not grasp the algorithm, and they just calculate it wrong.
@BaileyParker—the LUHN algorithm doesn't require the number to be divisible by 10 (or any particular number), it simply applies a formula to generate a value from the digits then looks at the last digit of the value (it uses %10, not /10). It's used by all cards in use.
M
Martijn Scheffer

In javascript:

function detectCardType(number) {
    var re = {
        electron: /^(4026|417500|4405|4508|4844|4913|4917)\d+$/,
        maestro: /^(5018|5020|5038|5612|5893|6304|6759|6761|6762|6763|0604|6390)\d+$/,
        dankort: /^(5019)\d+$/,
        interpayment: /^(636)\d+$/,
        unionpay: /^(62|88)\d+$/,
        visa: /^4[0-9]{12}(?:[0-9]{3})?$/,
        mastercard: /^5[1-5][0-9]{14}$/,
        amex: /^3[47][0-9]{13}$/,
        diners: /^3(?:0[0-5]|[68][0-9])[0-9]{11}$/,
        discover: /^6(?:011|5[0-9]{2})[0-9]{12}$/,
        jcb: /^(?:2131|1800|35\d{3})\d{11}$/
    }

    for(var key in re) {
        if(re[key].test(number)) {
            return key
        }
    }
}

Unit test:

describe('CreditCard', function() {
    describe('#detectCardType', function() {

        var cards = {
            '8800000000000000': 'UNIONPAY',

            '4026000000000000': 'ELECTRON',
            '4175000000000000': 'ELECTRON',
            '4405000000000000': 'ELECTRON',
            '4508000000000000': 'ELECTRON',
            '4844000000000000': 'ELECTRON',
            '4913000000000000': 'ELECTRON',
            '4917000000000000': 'ELECTRON',

            '5019000000000000': 'DANKORT',

            '5018000000000000': 'MAESTRO',
            '5020000000000000': 'MAESTRO',
            '5038000000000000': 'MAESTRO',
            '5612000000000000': 'MAESTRO',
            '5893000000000000': 'MAESTRO',
            '6304000000000000': 'MAESTRO',
            '6759000000000000': 'MAESTRO',
            '6761000000000000': 'MAESTRO',
            '6762000000000000': 'MAESTRO',
            '6763000000000000': 'MAESTRO',
            '0604000000000000': 'MAESTRO',
            '6390000000000000': 'MAESTRO',

            '3528000000000000': 'JCB',
            '3589000000000000': 'JCB',
            '3529000000000000': 'JCB',

            '6360000000000000': 'INTERPAYMENT',

            '4916338506082832': 'VISA',
            '4556015886206505': 'VISA',
            '4539048040151731': 'VISA',
            '4024007198964305': 'VISA',
            '4716175187624512': 'VISA',

            '5280934283171080': 'MASTERCARD',
            '5456060454627409': 'MASTERCARD',
            '5331113404316994': 'MASTERCARD',
            '5259474113320034': 'MASTERCARD',
            '5442179619690834': 'MASTERCARD',

            '6011894492395579': 'DISCOVER',
            '6011388644154687': 'DISCOVER',
            '6011880085013612': 'DISCOVER',
            '6011652795433988': 'DISCOVER',
            '6011375973328347': 'DISCOVER',

            '345936346788903': 'AMEX',
            '377669501013152': 'AMEX',
            '373083634595479': 'AMEX',
            '370710819865268': 'AMEX',
            '371095063560404': 'AMEX'
        };

        Object.keys(cards).forEach(function(number) {
            it('should detect card ' + number + ' as ' + cards[number], function() {
                Basket.detectCardType(number).should.equal(cards[number]);
            });
        });
    });
});

@jolly.exe - Your fiddle returns undefined for all tests. Doesn't work :(
@ShadeTreeDeveloper just enter any value eg. 372176090165471 for AMAX in text field
@jolly.exe I see... I was hoping for something that would format as I type (off the keyup event). The fiddle does work when I enter a full number.
I ended up writing this bit of code to do the input formatting and validation that I wanted. quercusv.github.io/smartForm
do you know how to detect v-pay and bancontact card numbers? Thanks
W
William Desportes

Updated: 15th June 2016 (as an ultimate solution currently)

Please note that I even give vote up for the one is top voted, but to make it clear these are the regexps actually works i tested it with thousands of real BIN codes. The most important is to use start strings (^) otherwise it will give false results in real world!

JCB ^(?:2131|1800|35)[0-9]{0,}$ Start with: 2131, 1800, 35 (3528-3589)

American Express ^3[47][0-9]{0,}$ Start with: 34, 37

Diners Club ^3(?:0[0-59]{1}|[689])[0-9]{0,}$ Start with: 300-305, 309, 36, 38-39

Visa ^4[0-9]{0,}$ Start with: 4

MasterCard ^(5[1-5]|222[1-9]|22[3-9]|2[3-6]|27[01]|2720)[0-9]{0,}$ Start with: 2221-2720, 51-55

Maestro ^(5[06789]|6)[0-9]{0,}$ Maestro always growing in the range: 60-69, started with / not something else, but starting 5 must be encoded as mastercard anyway. Maestro cards must be detected in the end of the code because some others has in the range of 60-69. Please look at the code.

Discover ^(6011|65|64[4-9]|62212[6-9]|6221[3-9]|622[2-8]|6229[01]|62292[0-5])[0-9]{0,}$ Discover quite difficult to code, start with: 6011, 622126-622925, 644-649, 65

In javascript I use this function. This is good when u assign it to an onkeyup event and it give result as soon as possible.

function cc_brand_id(cur_val) {
    // the regular expressions check for possible matches as you type, hence the OR operators based on the number of chars
    // regexp string length {0} provided for soonest detection of beginning of the card numbers this way it could be used for BIN CODE detection also

    //JCB
    jcb_regex = new RegExp('^(?:2131|1800|35)[0-9]{0,}$'); //2131, 1800, 35 (3528-3589)
    // American Express
    amex_regex = new RegExp('^3[47][0-9]{0,}$'); //34, 37
    // Diners Club
    diners_regex = new RegExp('^3(?:0[0-59]{1}|[689])[0-9]{0,}$'); //300-305, 309, 36, 38-39
    // Visa
    visa_regex = new RegExp('^4[0-9]{0,}$'); //4
    // MasterCard
    mastercard_regex = new RegExp('^(5[1-5]|222[1-9]|22[3-9]|2[3-6]|27[01]|2720)[0-9]{0,}$'); //2221-2720, 51-55
    maestro_regex = new RegExp('^(5[06789]|6)[0-9]{0,}$'); //always growing in the range: 60-69, started with / not something else, but starting 5 must be encoded as mastercard anyway
    //Discover
    discover_regex = new RegExp('^(6011|65|64[4-9]|62212[6-9]|6221[3-9]|622[2-8]|6229[01]|62292[0-5])[0-9]{0,}$');
    ////6011, 622126-622925, 644-649, 65


    // get rid of anything but numbers
    cur_val = cur_val.replace(/\D/g, '');

    // checks per each, as their could be multiple hits
    //fix: ordering matter in detection, otherwise can give false results in rare cases
    var sel_brand = "unknown";
    if (cur_val.match(jcb_regex)) {
        sel_brand = "jcb";
    } else if (cur_val.match(amex_regex)) {
        sel_brand = "amex";
    } else if (cur_val.match(diners_regex)) {
        sel_brand = "diners_club";
    } else if (cur_val.match(visa_regex)) {
        sel_brand = "visa";
    } else if (cur_val.match(mastercard_regex)) {
        sel_brand = "mastercard";
    } else if (cur_val.match(discover_regex)) {
        sel_brand = "discover";
    } else if (cur_val.match(maestro_regex)) {
        if (cur_val[0] == '5') { //started 5 must be mastercard
            sel_brand = "mastercard";
        } else {
            sel_brand = "maestro"; //maestro is all 60-69 which is not something else, thats why this condition in the end
        }
    }

    return sel_brand;
}

Here you can play with it:

http://jsfiddle.net/upN3L/69/

For PHP use this function, this detects some sub VISA/MC cards too:

/**
  * Obtain a brand constant from a PAN
  *
  * @param string $pan               Credit card number
  * @param bool   $include_sub_types Include detection of sub visa brands
  * @return string
  */
public static function getCardBrand($pan, $include_sub_types = false)
{
    //maximum length is not fixed now, there are growing number of CCs has more numbers in length, limiting can give false negatives atm

    //these regexps accept not whole cc numbers too
    //visa
    $visa_regex = "/^4[0-9]{0,}$/";
    $vpreca_regex = "/^428485[0-9]{0,}$/";
    $postepay_regex = "/^(402360|402361|403035|417631|529948){0,}$/";
    $cartasi_regex = "/^(432917|432930|453998)[0-9]{0,}$/";
    $entropay_regex = "/^(406742|410162|431380|459061|533844|522093)[0-9]{0,}$/";
    $o2money_regex = "/^(422793|475743)[0-9]{0,}$/";

    // MasterCard
    $mastercard_regex = "/^(5[1-5]|222[1-9]|22[3-9]|2[3-6]|27[01]|2720)[0-9]{0,}$/";
    $maestro_regex = "/^(5[06789]|6)[0-9]{0,}$/";
    $kukuruza_regex = "/^525477[0-9]{0,}$/";
    $yunacard_regex = "/^541275[0-9]{0,}$/";

    // American Express
    $amex_regex = "/^3[47][0-9]{0,}$/";

    // Diners Club
    $diners_regex = "/^3(?:0[0-59]{1}|[689])[0-9]{0,}$/";

    //Discover
    $discover_regex = "/^(6011|65|64[4-9]|62212[6-9]|6221[3-9]|622[2-8]|6229[01]|62292[0-5])[0-9]{0,}$/";

    //JCB
    $jcb_regex = "/^(?:2131|1800|35)[0-9]{0,}$/";

    //ordering matter in detection, otherwise can give false results in rare cases
    if (preg_match($jcb_regex, $pan)) {
        return "jcb";
    }

    if (preg_match($amex_regex, $pan)) {
        return "amex";
    }

    if (preg_match($diners_regex, $pan)) {
        return "diners_club";
    }

    //sub visa/mastercard cards
    if ($include_sub_types) {
        if (preg_match($vpreca_regex, $pan)) {
            return "v-preca";
        }
        if (preg_match($postepay_regex, $pan)) {
            return "postepay";
        }
        if (preg_match($cartasi_regex, $pan)) {
            return "cartasi";
        }
        if (preg_match($entropay_regex, $pan)) {
            return "entropay";
        }
        if (preg_match($o2money_regex, $pan)) {
            return "o2money";
        }
        if (preg_match($kukuruza_regex, $pan)) {
            return "kukuruza";
        }
        if (preg_match($yunacard_regex, $pan)) {
            return "yunacard";
        }
    }

    if (preg_match($visa_regex, $pan)) {
        return "visa";
    }

    if (preg_match($mastercard_regex, $pan)) {
        return "mastercard";
    }

    if (preg_match($discover_regex, $pan)) {
        return "discover";
    }

    if (preg_match($maestro_regex, $pan)) {
        if ($pan[0] == '5') { //started 5 must be mastercard
            return "mastercard";
        }
        return "maestro"; //maestro is all 60-69 which is not something else, thats why this condition in the end

    }

    return "unknown"; //unknown for this system
}

And please note, that this is only CC number detection and not validation. That is separated, should be a Luhn check...
Where is Visa Electron, and why does the Maestro check return MasterCard in some cases? Shouldn't the MasterCard check that itself?
It fails to recognize this JCB test number as any of the types (3088514174175777), and identifies this test JCB number as diners_club (3096278649822922). Assuming this list of test card numbers are valid anyway (freeformatter.com/credit-card-number-generator-validator.html)
there are no documentation that starting 308 or 309 could be a JCB card
+1 for providing cc type detection code, which is what you typically want to do for the ux - the regex for the new range on MC needs a small tweek: /^(5[1-5]|222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{0,}$/
W
William Desportes
public string GetCreditCardType(string CreditCardNumber)
{
    Regex regVisa = new Regex("^4[0-9]{12}(?:[0-9]{3})?$");
    Regex regMaster = new Regex("^5[1-5][0-9]{14}$");
    Regex regExpress = new Regex("^3[47][0-9]{13}$");
    Regex regDiners = new Regex("^3(?:0[0-5]|[68][0-9])[0-9]{11}$");
    Regex regDiscover = new Regex("^6(?:011|5[0-9]{2})[0-9]{12}$");
    Regex regJCB = new Regex("^(?:2131|1800|35\\d{3})\\d{11}$");


    if (regVisa.IsMatch(CreditCardNumber))
        return "VISA";
    else if (regMaster.IsMatch(CreditCardNumber))
        return "MASTER";
    else  if (regExpress.IsMatch(CreditCardNumber))
        return "AEXPRESS";
    else if (regDiners.IsMatch(CreditCardNumber))
        return "DINERS";
    else if (regDiscover.IsMatch(CreditCardNumber))
        return "DISCOVERS";
    else if (regJCB.IsMatch(CreditCardNumber))
        return "JCB";
    else
        return "invalid";
}

Here is the function to check Credit card type using Regex , c#


W
William Desportes

Check this out:

http://www.breakingpar.com/bkp/home.nsf/0/87256B280015193F87256CC70060A01B

function isValidCreditCard(type, ccnum) {
    /* Visa: length 16, prefix 4, dashes optional.
    Mastercard: length 16, prefix 51-55, dashes optional.
    Discover: length 16, prefix 6011, dashes optional.
    American Express: length 15, prefix 34 or 37.
    Diners: length 14, prefix 30, 36, or 38. */

    var re = new Regex({
        "visa": "/^4\d{3}-?\d{4}-?\d{4}-?\d",
        "mc": "/^5[1-5]\d{2}-?\d{4}-?\d{4}-?\d{4}$/",
        "disc": "/^6011-?\d{4}-?\d{4}-?\d{4}$/",
        "amex": "/^3[47]\d{13}$/",
        "diners": "/^3[068]\d{12}$/"
    }[type.toLowerCase()])

    if (!re.test(ccnum)) return false;
    // Remove all dashes for the checksum checks to eliminate negative numbers
    ccnum = ccnum.split("-").join("");
    // Checksum ("Mod 10")
    // Add even digits in even length strings or odd digits in odd length strings.
    var checksum = 0;
    for (var i = (2 - (ccnum.length % 2)); i <= ccnum.length; i += 2) {
        checksum += parseInt(ccnum.charAt(i - 1));
    }
    // Analyze odd digits in even length strings or even digits in odd length strings.
    for (var i = (ccnum.length % 2) + 1; i < ccnum.length; i += 2) {
        var digit = parseInt(ccnum.charAt(i - 1)) * 2;
        if (digit < 10) { checksum += digit; } else { checksum += (digit - 9); }
    }
    if ((checksum % 10) == 0) return true;
    else return false;
}

Mastercard has upgraded and they now use numbers that start with 2[...] and so on. Please update your code. You may like to use this /^(?:5[1-5]|5[1-5][0-9]{14}|2(22[1-9][0-9]{12}|2[3-9][0-9]{13}|[3-6][0-9]{14}|7[0-1][0-9]{13}|720[0-9]{12}))$/
F
Fivell

recently I needed such functionality, I was porting Zend Framework Credit Card Validator to ruby. ruby gem: https://github.com/Fivell/credit_card_validations zend framework: https://github.com/zendframework/zf2/blob/master/library/Zend/Validator/CreditCard.php

They both use INN ranges for detecting type. Here you can read about INN

According to this you can detect credit card alternatively (without regexps,but declaring some rules about prefixes and possible length)

So we have next rules for most used cards

########  most used brands #########

    visa: [
        {length: [13, 16], prefixes: ['4']}
    ],
    mastercard: [
        {length: [16], prefixes: ['51', '52', '53', '54', '55']}
    ],

    amex: [
        {length: [15], prefixes: ['34', '37']}
    ],
    ######## other brands ########
    diners: [
        {length: [14], prefixes: ['300', '301', '302', '303', '304', '305', '36', '38']},
    ],

    #There are Diners Club (North America) cards that begin with 5. These are a joint venture between Diners Club and MasterCard, and are processed like a MasterCard
    # will be removed in next major version

    diners_us: [
        {length: [16], prefixes: ['54', '55']}
    ],

    discover: [
        {length: [16], prefixes: ['6011', '644', '645', '646', '647', '648',
                                  '649', '65']}
    ],

    jcb: [
        {length: [16], prefixes: ['3528', '3529', '353', '354', '355', '356', '357', '358', '1800', '2131']}
    ],


    laser: [
        {length: [16, 17, 18, 19], prefixes: ['6304', '6706', '6771']}
    ],

    solo: [
        {length: [16, 18, 19], prefixes: ['6334', '6767']}
    ],

    switch: [
        {length: [16, 18, 19], prefixes: ['633110', '633312', '633304', '633303', '633301', '633300']}

    ],

    maestro: [
        {length: [12, 13, 14, 15, 16, 17, 18, 19], prefixes: ['5010', '5011', '5012', '5013', '5014', '5015', '5016', '5017', '5018',
                                                              '502', '503', '504', '505', '506', '507', '508',
                                                              '6012', '6013', '6014', '6015', '6016', '6017', '6018', '6019',
                                                              '602', '603', '604', '605', '6060',
                                                              '677', '675', '674', '673', '672', '671', '670',
                                                              '6760', '6761', '6762', '6763', '6764', '6765', '6766', '6768', '6769']}
    ],

    # Luhn validation are skipped for union pay cards because they have unknown generation algoritm
    unionpay: [
        {length: [16, 17, 18, 19], prefixes: ['622', '624', '625', '626', '628'], skip_luhn: true}
    ],

    dankrot: [
        {length: [16], prefixes: ['5019']}
    ],

    rupay: [
        {length: [16], prefixes: ['6061', '6062', '6063', '6064', '6065', '6066', '6067', '6068', '6069', '607', '608'], skip_luhn: true}
    ]

}

Then by searching prefix and comparing length you can detect credit card brand. Also don't forget about luhn algoritm (it is descibed here http://en.wikipedia.org/wiki/Luhn).

UPDATE

updated list of rules can be found here https://raw.githubusercontent.com/Fivell/credit_card_validations/master/lib/data/brands.yaml


Very illustrative. VISA cards may be 13 digits long.
@HermanKan, no VISA website says it should be 16 length, I think long time ago it could be 13, but not nowadays
I think it is legacy support
@HermanKan, there is one more thing, VISA has VPay cards and accroding to wikipedia Visa's VPay brand can specify PAN lengths from 13 to 19 digits an so card number of more than 16 digits are now being seen.
@Ethan, check last link in my updated answer raw.githubusercontent.com/Fivell/credit_card_validations/master/…
R
RoLYroLLs

Here's Complete C# or VB code for all kinds of CC related things on codeproject.

IsValidNumber

GetCardTypeFromNumber

GetCardTestNumber

PassesLuhnTest

This article has been up for a couple years with no negative comments.


@barett - fixed it. looks like they moved it from 'aspnet' category to 'validation' category which changed the link
Link is broken. Maybe this is the same utility? codeproject.com/Articles/20271/…
That codeproject code is from 2007. Warning, It may be outdated.
N
Nick

Compact javascript version

    var getCardType = function (number) {
        var cards = {
            visa: /^4[0-9]{12}(?:[0-9]{3})?$/,
            mastercard: /^5[1-5][0-9]{14}$/,
            amex: /^3[47][0-9]{13}$/,
            diners: /^3(?:0[0-5]|[68][0-9])[0-9]{11}$/,
            discover: /^6(?:011|5[0-9]{2})[0-9]{12}$/,
            jcb: /^(?:2131|1800|35\d{3})\d{11}$/
        };
        for (var card in cards) {
            if (cards[card].test(number)) {
                return card;
            }
        }
    };

a
angelcool.net

Anatoliy's answer in PHP:

 public static function detectCardType($num)
 {
    $re = array(
        "visa"       => "/^4[0-9]{12}(?:[0-9]{3})?$/",
        "mastercard" => "/^5[1-5][0-9]{14}$/",
        "amex"       => "/^3[47][0-9]{13}$/",
        "discover"   => "/^6(?:011|5[0-9]{2})[0-9]{12}$/",
    );

    if (preg_match($re['visa'],$num))
    {
        return 'visa';
    }
    else if (preg_match($re['mastercard'],$num))
    {
        return 'mastercard';
    }
    else if (preg_match($re['amex'],$num))
    {
        return 'amex';
    }
    else if (preg_match($re['discover'],$num))
    {
        return 'discover';
    }
    else
    {
        return false;
    }
 }

W
William Desportes

Here is a php class function returns CCtype by CCnumber.
This code not validates the card or not runs Luhn algorithm only try to find credit card type based on table in this page. basicly uses CCnumber length and CCcard prefix to determine CCcard type.

<?php
class CreditcardType
{
    public static $creditcardTypes = [
        [
            'Name' => 'American Express',
            'cardLength' => [15],
            'cardPrefix' => ['34', '37'],
        ], [
            'Name' => 'Maestro',
            'cardLength' => [12, 13, 14, 15, 16, 17, 18, 19],
            'cardPrefix' => ['5018', '5020', '5038', '6304', '6759', '6761', '6763'],
        ], [
            'Name' => 'Mastercard',
            'cardLength' => [16],
            'cardPrefix' => ['51', '52', '53', '54', '55'],
        ], [
            'Name' => 'Visa',
            'cardLength' => [13, 16],
            'cardPrefix' => ['4'],
        ], [
            'Name' => 'JCB',
            'cardLength' => [16],
            'cardPrefix' => ['3528', '3529', '353', '354', '355', '356', '357', '358'],
        ], [
            'Name' => 'Discover',
            'cardLength' => [16],
            'cardPrefix' => ['6011', '622126', '622127', '622128', '622129', '62213','62214', '62215', '62216', '62217', '62218', '62219','6222', '6223', '6224', '6225', '6226', '6227', '6228','62290', '62291', '622920', '622921', '622922', '622923','622924', '622925', '644', '645', '646', '647', '648','649', '65'],
        ], [
            'Name' => 'Solo',
            'cardLength' => [16, 18, 19],
            'cardPrefix' => ['6334', '6767'],
        ], [
            'Name' => 'Unionpay',
            'cardLength' => [16, 17, 18, 19],
            'cardPrefix' => ['622126', '622127', '622128', '622129', '62213', '62214','62215', '62216', '62217', '62218', '62219', '6222', '6223','6224', '6225', '6226', '6227', '6228', '62290', '62291','622920', '622921', '622922', '622923', '622924', '622925'],
        ], [
            'Name' => 'Diners Club',
            'cardLength' => [14],
            'cardPrefix' => ['300', '301', '302', '303', '304', '305', '36'],
        ], [
            'Name' => 'Diners Club US',
            'cardLength' => [16],
            'cardPrefix' => ['54', '55'],
        ], [
            'Name' => 'Diners Club Carte Blanche',
            'cardLength' => [14],
            'cardPrefix' => ['300', '305'],
        ], [
            'Name' => 'Laser',
            'cardLength' => [16, 17, 18, 19],
            'cardPrefix' => ['6304', '6706', '6771', '6709'],
        ],
    ];

    public static function getType($CCNumber)
    {
        $CCNumber = trim($CCNumber);
        $type = 'Unknown';
        foreach (CreditcardType::$creditcardTypes as $card) {
            if (! in_array(strlen($CCNumber), $card['cardLength'])) {
                continue;
            }
            $prefixes = '/^(' . implode('|', $card['cardPrefix']) . ')/';
            if (preg_match($prefixes, $CCNumber) == 1) {
                $type = $card['Name'];
                break;
            }
        }
        return $type;
    }
}


Note that this does not handle the new Mastercard prefixes (2221–2720) that were introduced in 2017.
G
Gajus

The first numbers of the credit card can be used to approximate the vendor:

Visa: 49,44 or 47

Visa electron: 42, 45, 48, 49

MasterCard: 51

Amex:34

Diners: 30, 36, 38

JCB: 35


These ranges have been updated majorly, Card vendor companies have added way more ranges than mentioned in the post.
6
6 revs, 2 users 95%

In Card Range Recognition (CRR), a drawback with algorithms that use a series of regex or other hard-coded ranges, is that the BINs/IINs do change over time in my experience. The co-branding of cards is an ongoing complication. Different Card Acquirers / merchants may need you treat the same card differently, depending on e.g. geolocation.

Additionally, in the last few years with e.g. UnionPay cards in wider circulation, existing models do not cope with new ranges that sometimes interleave with broader ranges that they supersede. Knowing the geography your system needs to cover may help, as some ranges are restricted to use in particular countries. For example, ranges 62 include some AAA sub-ranges in the US, but if your merchant base is outside the US, you may be able to treat all 62 as UnionPay. You may be also asked to treat a card differently based on merchant location. E.g. to treat certain UK cards as debit domestically, but as credit internationally.

There are very useful set of rules maintained by one major Acquiring Bank. E.g. https://www.barclaycard.co.uk/business/files/BIN-Rules-EIRE.pdf and https://www.barclaycard.co.uk/business/files/BIN-Rules-UK.pdf. (Valid links as of June 2017, thanks to the user who provided a link to updated reference.) But be aware of the caveat that, while these CRR rules may represent the Card Issuing universe as it applies to the merchants acquired by that entity, it does not include e.g. ranges identified as CUP/UPI.

These comments apply to magnetic stripe (MagStripe) or PKE (Pan Key Entry) scenarios. The situation is different again in the ICC/EMV world.

Update: Other answers on this page (and also the linked WikiPedia page) have JCB as always 16 long. However, in my company we have a dedicated team of engineers who certify our POS devices and software across multiple acquiring banks and geographies. The most recent Certification Pack of cards this team have from JCB, had a pass case for a 19 long PAN.


Hi @CaiqueOliveira, see updated links. Thanks to mac9416 who provided a link to updated BIN-Rules reference.
Thanks @mac9416, for the updated BIN-Rules reference.
G
Gajus

Do not try to detect credit card type as part of processing a payment. You are risking of declining valid transactions.

If you need to provide information to your payment processor (e.g. PayPal credit card object requires to name the card type), then guess it from the least information available, e.g.

$credit_card['pan'] = preg_replace('/[^0-9]/', '', $credit_card['pan']);
$inn = (int) mb_substr($credit_card['pan'], 0, 2);

// @see http://en.wikipedia.org/wiki/List_of_Bank_Identification_Numbers#Overview
if ($inn >= 40 && $inn <= 49) {
    $type = 'visa';
} else if ($inn >= 51 && $inn <= 55) {
    $type = 'mastercard';
} else if ($inn >= 60 && $inn <= 65) {
    $type = 'discover';
} else if ($inn >= 34 && $inn <= 37) {
    $type = 'amex';
} else {
    throw new \UnexpectedValueException('Unsupported card type.');
}

This implementation (using only the first two digits) is enough to identify all of the major (and in PayPal's case all of the supported) card schemes. In fact, you might want to skip the exception altogether and default to the most popular card type. Let the payment gateway/processor tell you if there is a validation error in response to your request.

The reality is that your payment gateway does not care about the value you provide.


This is simply untrue. I know of 3 different providers that DO require card types to be passed in, and if you do not pass it in, the transaction will fail.
@EdDeGagne - "does not care what value" is not the same as "does not care if passed in".
Where did I specify either? I simply mentioned that there are providers in use that require YOU to pass in the CC type, nothing more.
you cant simplify this complex issue, but usually payment providers do not require for you to suggest card type, they have their own method to detect
D
Daisy R.

Swift 2.1 Version of Usman Y's answer. Use a print statement to verify so call by some string value

print(self.validateCardType(self.creditCardField.text!))

func validateCardType(testCard: String) -> String {

    let regVisa = "^4[0-9]{12}(?:[0-9]{3})?$"
    let regMaster = "^5[1-5][0-9]{14}$"
    let regExpress = "^3[47][0-9]{13}$"
    let regDiners = "^3(?:0[0-5]|[68][0-9])[0-9]{11}$"
    let regDiscover = "^6(?:011|5[0-9]{2})[0-9]{12}$"
    let regJCB = "^(?:2131|1800|35\\d{3})\\d{11}$"


    let regVisaTest = NSPredicate(format: "SELF MATCHES %@", regVisa)
    let regMasterTest = NSPredicate(format: "SELF MATCHES %@", regMaster)
    let regExpressTest = NSPredicate(format: "SELF MATCHES %@", regExpress)
    let regDinersTest = NSPredicate(format: "SELF MATCHES %@", regDiners)
    let regDiscoverTest = NSPredicate(format: "SELF MATCHES %@", regDiscover)
    let regJCBTest = NSPredicate(format: "SELF MATCHES %@", regJCB)


    if regVisaTest.evaluateWithObject(testCard){
        return "Visa"
    }
    else if regMasterTest.evaluateWithObject(testCard){
        return "MasterCard"
    }

    else if regExpressTest.evaluateWithObject(testCard){
        return "American Express"
    }

    else if regDinersTest.evaluateWithObject(testCard){
        return "Diners Club"
    }

    else if regDiscoverTest.evaluateWithObject(testCard){
        return "Discover"
    }

    else if regJCBTest.evaluateWithObject(testCard){
        return "JCB"
    }

    return ""

}

N
Nagama Inamdar

Stripe has provided this fantastic javascript library for card scheme detection. Let me add few code snippets and show you how to use it.

Firstly Include it to your web page as

<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery.payment/1.2.3/jquery.payment.js " ></script>

Secondly use the function cardType for detecting the card scheme.

$(document).ready(function() {              
            var type = $.payment.cardType("4242 4242 4242 4242"); //test card number
            console.log(type);                                   
}); 

Here are the reference links for more examples and demos.

Stripe blog for jquery.payment.js Github repository


V
Vidyalaxmi

In swift you can create an enum to detect the credit card type.

enum CreditCardType: Int { // Enum which encapsulates different card types and method to find the type of card.

case Visa
case Master
case Amex
case Discover

func validationRegex() -> String {
    var regex = ""
    switch self {
    case .Visa:
        regex = "^4[0-9]{6,}$"

    case .Master:
        regex = "^5[1-5][0-9]{5,}$"

    case .Amex:
        regex = "^3[47][0-9]{13}$"

    case .Discover:
        regex = "^6(?:011|5[0-9]{2})[0-9]{12}$"
    }

    return regex
}

func validate(cardNumber: String) -> Bool {
    let predicate = NSPredicate(format: "SELF MATCHES %@", validationRegex())
    return predicate.evaluateWithObject(cardNumber)
}

// Method returns the credit card type for given card number
static func cardTypeForCreditCardNumber(cardNumber: String) -> CreditCardType?  {
    var creditCardType: CreditCardType?

    var index = 0
    while let cardType = CreditCardType(rawValue: index) {
        if cardType.validate(cardNumber) {
            creditCardType = cardType
            break
        } else {
            index++
        }
    }
    return creditCardType
  }
}

Call the method CreditCardType.cardTypeForCreditCardNumber("#card number") which returns CreditCardType enum value.


Z
ZurabWeb

My solution with jQuery:

function detectCreditCardType() {
    var type = new Array;
    type[1] = '^4[0-9]{12}(?:[0-9]{3})?$';      // visa
    type[2] = '^5[1-5][0-9]{14}$';              // mastercard
    type[3] = '^6(?:011|5[0-9]{2})[0-9]{12}$';  // discover
    type[4] = '^3[47][0-9]{13}$';               // amex

    var ccnum = $('.creditcard').val().replace(/[^\d.]/g, '');
    var returntype = 0;

    $.each(type, function(idx, re) {
        var regex = new RegExp(re);
        if(regex.test(ccnum) && idx>0) {
            returntype = idx;
        }
    });

    return returntype;
}

In case 0 is returned, credit card type is undetected.

"creditcard" class should be added to the credit card input field.


Variation of existing answers.
Yes, I used the code from the above answers, IMPROVED it and posted it here. Thanks for the downvote...
You should have (a) suggested this as an improvement to the existing code, (b) written the appropriate contributions, or (c) reference the sources that you have used to write the regular expressions.
Gajus, I believe I helped the community the way I could at that moment, please stop telling me I should've done something for someone. I did what I though could've been helpful.
S
ShadeTreeDeveloper

I searched around quite a bit for credit card formatting and phone number formatting. Found lots of good tips but nothing really suited my exact desires so I created this bit of code. You use it like this:

var sf = smartForm.formatCC(myInputString);
var cardType = sf.cardType;

E
Emanuel

A javascript improve of @Anatoliy answer

function getCardType (number) { const numberFormated = number.replace(/\D/g, '') var patterns = { VISA: /^4[0-9]{12}(?:[0-9]{3})?$/, MASTER: /^5[1-5][0-9]{14}$/, AMEX: /^3[47][0-9]{13}$/, ELO: /^((((636368)|(438935)|(504175)|(451416)|(636297))\d{0,10})|((5067)|(4576)|(4011))\d{0,12})$/, AURA: /^(5078\d{2})(\d{2})(\d{11})$/, JCB: /^(?:2131|1800|35\d{3})\d{11}$/, DINERS: /^3(?:0[0-5]|[68][0-9])[0-9]{11}$/, DISCOVERY: /^6(?:011|5[0-9]{2})[0-9]{12}$/, HIPERCARD: /^(606282\d{10}(\d{3})?)|(3841\d{15})$/, ELECTRON: /^(4026|417500|4405|4508|4844|4913|4917)\d+$/, MAESTRO: /^(5018|5020|5038|5612|5893|6304|6759|6761|6762|6763|0604|6390)\d+$/, DANKORT: /^(5019)\d+$/, INTERPAYMENT: /^(636)\d+$/, UNIONPAY: /^(62|88)\d+$/, } for (var key in patterns) { if (patterns[key].test(numberFormated)) { return key } } } console.log(getCardType("4539 5684 7526 2091"))


Seems like 4508 doesn't belong to Visa electron Source: bincheck.org/visa-visa-electron?page=1 freebinchecker.com/VISA-electron-debit-card-bank
Please update MasterCard RegEx to accommodate the contemporary changes.
S
Saharat Sittipanya

Swift 5+

extension String {
    
    func isMatch(_ Regex: String) -> Bool {
        
        do {
            let regex = try NSRegularExpression(pattern: Regex)
            let results = regex.matches(in: self, range: NSRange(self.startIndex..., in: self))
            return results.map {
                String(self[Range($0.range, in: self)!])
            }.count > 0
        } catch {
            return false
        }
        
    }
    
    func getCreditCardType() -> String? {
        
        let VISA_Regex = "^4[0-9]{6,}$"
        let MasterCard_Regex = "^5[1-5][0-9]{5,}|222[1-9][0-9]{3,}|22[3-9][0-9]{4,}|2[3-6][0-9]{5,}|27[01][0-9]{4,}|2720[0-9]{3,}$"
        let AmericanExpress_Regex = "^3[47][0-9]{5,}$"
        let DinersClub_Regex = "^3(?:0[0-5]|[68][0-9])[0-9]{4,}$"
        let Discover_Regex = "^6(?:011|5[0-9]{2})[0-9]{3,}$"
        let JCB_Regex = "^(?:2131|1800|35[0-9]{3})[0-9]{3,}$"
        
        if self.isMatch(VISA_Regex) {
            return "VISA"
        } else if self.isMatch(MasterCard_Regex) {
            return "MasterCard"
        } else if self.isMatch(AmericanExpress_Regex) {
            return "AmericanExpress"
        } else if self.isMatch(DinersClub_Regex) {
            return "DinersClub"
        } else if self.isMatch(Discover_Regex) {
            return "Discover"
        } else if self.isMatch(JCB_Regex) {
            return "JCB"
        } else {
            return nil
        }
        
    }
    
}

Use.

"1234123412341234".getCreditCardType()

P
Parvez
// abobjects.com, parvez ahmad ab bulk mailer
use below script

function isValidCreditCard2(type, ccnum) {
       if (type == "Visa") {
          // Visa: length 16, prefix 4, dashes optional.
          var re = /^4\d{3}?\d{4}?\d{4}?\d{4}$/;
       } else if (type == "MasterCard") {
          // Mastercard: length 16, prefix 51-55, dashes optional.
          var re = /^5[1-5]\d{2}?\d{4}?\d{4}?\d{4}$/;
       } else if (type == "Discover") {
          // Discover: length 16, prefix 6011, dashes optional.
          var re = /^6011?\d{4}?\d{4}?\d{4}$/;
       } else if (type == "AmEx") {
          // American Express: length 15, prefix 34 or 37.
          var re = /^3[4,7]\d{13}$/;
       } else if (type == "Diners") {
          // Diners: length 14, prefix 30, 36, or 38.
          var re = /^3[0,6,8]\d{12}$/;
       }
       if (!re.test(ccnum)) return false;
       return true;
       /*
       // Remove all dashes for the checksum checks to eliminate negative numbers
       ccnum = ccnum.split("-").join("");
       // Checksum ("Mod 10")
       // Add even digits in even length strings or odd digits in odd length strings.
       var checksum = 0;
       for (var i=(2-(ccnum.length % 2)); i<=ccnum.length; i+=2) {
          checksum += parseInt(ccnum.charAt(i-1));
       }
       // Analyze odd digits in even length strings or even digits in odd length strings.
       for (var i=(ccnum.length % 2) + 1; i<ccnum.length; i+=2) {
          var digit = parseInt(ccnum.charAt(i-1)) * 2;
          if (digit < 10) { checksum += digit; } else { checksum += (digit-9); }
       }
       if ((checksum % 10) == 0) return true; else return false;
       */

    }
jQuery.validator.addMethod("isValidCreditCard", function(postalcode, element) { 
    return isValidCreditCard2($("#cardType").val(), $("#cardNum").val()); 

}, "<br>credit card is invalid");


     Type</td>
                                          <td class="text">&nbsp; <form:select path="cardType" cssclass="fields" style="border: 1px solid #D5D5D5;padding: 0px 0px 0px 0px;width: 130px;height: 22px;">
                                              <option value="SELECT">SELECT</option>
                                              <option value="MasterCard">Mastercard</option>
                                              <option value="Visa">Visa</option>
                                               <option value="AmEx">American Express</option>
                                              <option value="Discover">Discover</option>
                                            </form:select> <font color="#FF0000">*</font> 

$("#signupForm").validate({

    rules:{
       companyName:{required: true},
       address1:{required: true},
       city:{required: true},
       state:{required: true},
       zip:{required: true},
       country:{required: true},
       chkAgree:{required: true},
       confPassword:{required: true},
       lastName:{required: true},
       firstName:{required: true},
       ccAddress1:{required: true},
       ccZip:{         
           postalcode : true
       },
       phone:{required: true},
       email:{
           required: true,
           email: true
           },
       userName:{
           required: true,
           minlength: 6
           },
       password:{
           required: true,
           minlength: 6
           },          
       cardNum:{           
            isValidCreditCard : true
       },

The question is about the algorithm to check a credit card, not a specific implementation. What does this code do?
P
Pinch

Just a little spoon feeding:

$("#CreditCardNumber").focusout(function () {


        var regVisa = /^4[0-9]{12}(?:[0-9]{3})?$/;
        var regMasterCard = /^5[1-5][0-9]{14}$/;
        var regAmex = /^3[47][0-9]{13}$/;
        var regDiscover = /^6(?:011|5[0-9]{2})[0-9]{12}$/;

        if (regVisa.test($(this).val())) {
            $("#CCImage").html("<img height='40px' src='@Url.Content("~/images/visa.png")'>");          

        }

        else if (regMasterCard.test($(this).val())) {
        $("#CCImage").html("<img height='40px' src='@Url.Content("~/images/mastercard.png")'>");

        }

        else if (regAmex.test($(this).val())) {

           $("#CCImage").html("<img height='40px' src='@Url.Content("~/images/amex.png")'>");

        }
         else if (regDiscover.test($(this).val())) {

           $("#CCImage").html("<img height='40px' src='@Url.Content("~/images/discover.png")'>");

        }
        else {
        $("#CCImage").html("NA");

        }

    });

r
radtek

Here is an example of some boolean functions written in Python that return True if the card is detected as per the function name.

def is_american_express(cc_number):
    """Checks if the card is an american express. If us billing address country code, & is_amex, use vpos
    https://en.wikipedia.org/wiki/Bank_card_number#cite_note-GenCardFeatures-3
    :param cc_number: unicode card number
    """
    return bool(re.match(r'^3[47][0-9]{13}$', cc_number))


def is_visa(cc_number):
    """Checks if the card is a visa, begins with 4 and 12 or 15 additional digits.
    :param cc_number: unicode card number
    """

    # Standard Visa is 13 or 16, debit can be 19
    if bool(re.match(r'^4', cc_number)) and len(cc_number) in [13, 16, 19]:
        return True

    return False


def is_mastercard(cc_number):
    """Checks if the card is a mastercard. Begins with 51-55 or 2221-2720 and 16 in length.
    :param cc_number: unicode card number
    """
    if len(cc_number) == 16 and cc_number.isdigit():  # Check digit, before cast to int
        return bool(re.match(r'^5[1-5]', cc_number)) or int(cc_number[:4]) in range(2221, 2721)
    return False


def is_discover(cc_number):
    """Checks if the card is discover, re would be too hard to maintain. Not a supported card.
    :param cc_number: unicode card number
    """
    if len(cc_number) == 16:
        try:
            # return bool(cc_number[:4] == '6011' or cc_number[:2] == '65' or cc_number[:6] in range(622126, 622926))
            return bool(cc_number[:4] == '6011' or cc_number[:2] == '65' or 622126 <= int(cc_number[:6]) <= 622925)
        except ValueError:
            return False
    return False


def is_jcb(cc_number):
    """Checks if the card is a jcb. Not a supported card.
    :param cc_number: unicode card number
    """
    # return bool(re.match(r'^(?:2131|1800|35\d{3})\d{11}$', cc_number))  # wikipedia
    return bool(re.match(r'^35(2[89]|[3-8][0-9])[0-9]{12}$', cc_number))  # PawelDecowski


def is_diners_club(cc_number):
    """Checks if the card is a diners club. Not a supported card.
    :param cc_number: unicode card number
    """
    return bool(re.match(r'^3(?:0[0-6]|[68][0-9])[0-9]{11}$', cc_number))  # 0-5 = carte blance, 6 = international


def is_laser(cc_number):
    """Checks if the card is laser. Not a supported card.
    :param cc_number: unicode card number
    """
    return bool(re.match(r'^(6304|670[69]|6771)', cc_number))


def is_maestro(cc_number):
    """Checks if the card is maestro. Not a supported card.
    :param cc_number: unicode card number
    """
    possible_lengths = [12, 13, 14, 15, 16, 17, 18, 19]
    return bool(re.match(r'^(50|5[6-9]|6[0-9])', cc_number)) and len(cc_number) in possible_lengths


# Child cards

def is_visa_electron(cc_number):
    """Child of visa. Checks if the card is a visa electron. Not a supported card.
    :param cc_number: unicode card number
    """
    return bool(re.match(r'^(4026|417500|4508|4844|491(3|7))', cc_number)) and len(cc_number) == 16


def is_total_rewards_visa(cc_number):
    """Child of visa. Checks if the card is a Total Rewards Visa. Not a supported card.
    :param cc_number: unicode card number
    """
    return bool(re.match(r'^41277777[0-9]{8}$', cc_number))


def is_diners_club_carte_blanche(cc_number):
    """Child card of diners. Checks if the card is a diners club carte blance. Not a supported card.
    :param cc_number: unicode card number
    """
    return bool(re.match(r'^30[0-5][0-9]{11}$', cc_number))  # github PawelDecowski, jquery-creditcardvalidator


def is_diners_club_carte_international(cc_number):
    """Child card of diners. Checks if the card is a diners club international. Not a supported card.
    :param cc_number: unicode card number
    """
    return bool(re.match(r'^36[0-9]{12}$', cc_number))  # jquery-creditcardvalidator

A
Anoop M Maddasseri

The first six digits of a card number (including the initial MII digit) are known as the issuer identification number (IIN). These identify the card issuing institution that issued the card to the card holder. The rest of the number is allocated by the card issuer. The card number's length is its number of digits. Many card issuers print the entire IIN and account number on their card.

Based on the above facts I would like to keep a snippet of JAVA code to identify card brand.

Sample card types

public static final String AMERICAN_EXPRESS = "American Express";
public static final String DISCOVER = "Discover";
public static final String JCB = "JCB";
public static final String DINERS_CLUB = "Diners Club";
public static final String VISA = "Visa";
public static final String MASTERCARD = "MasterCard";
public static final String UNKNOWN = "Unknown";

Card Prefixes

// Based on http://en.wikipedia.org/wiki/Bank_card_number#Issuer_identification_number_.28IIN.29
public static final String[] PREFIXES_AMERICAN_EXPRESS = {"34", "37"};
public static final String[] PREFIXES_DISCOVER = {"60", "62", "64", "65"};
public static final String[] PREFIXES_JCB = {"35"};
public static final String[] PREFIXES_DINERS_CLUB = {"300", "301", "302", "303", "304", "305", "309", "36", "38", "39"};
public static final String[] PREFIXES_VISA = {"4"};
public static final String[] PREFIXES_MASTERCARD = {
        "2221", "2222", "2223", "2224", "2225", "2226", "2227", "2228", "2229",
        "223", "224", "225", "226", "227", "228", "229",
        "23", "24", "25", "26",
        "270", "271", "2720",
        "50", "51", "52", "53", "54", "55"
    };

Check to see if the input number has any of the given prefixes.

public String getBrand(String number) {

String evaluatedType;
if (StripeTextUtils.hasAnyPrefix(number, PREFIXES_AMERICAN_EXPRESS)) {
    evaluatedType = AMERICAN_EXPRESS;
} else if (StripeTextUtils.hasAnyPrefix(number, PREFIXES_DISCOVER)) {
    evaluatedType = DISCOVER;
} else if (StripeTextUtils.hasAnyPrefix(number, PREFIXES_JCB)) {
    evaluatedType = JCB;
} else if (StripeTextUtils.hasAnyPrefix(number, PREFIXES_DINERS_CLUB)) {
    evaluatedType = DINERS_CLUB;
} else if (StripeTextUtils.hasAnyPrefix(number, PREFIXES_VISA)) {
    evaluatedType = VISA;
} else if (StripeTextUtils.hasAnyPrefix(number, PREFIXES_MASTERCARD)) {
    evaluatedType = MASTERCARD;
} else {
    evaluatedType = UNKNOWN;
}
    return evaluatedType;
}

Finally, The Utility method

/**
  * Check to see if the input number has any of the given prefixes.
  *
  * @param number the number to test
  * @param prefixes the prefixes to test against
  * @return {@code true} if number begins with any of the input prefixes
*/

public static boolean hasAnyPrefix(String number, String... prefixes) {
  if (number == null) {
       return false;
  }
   for (String prefix : prefixes) {
       if (number.startsWith(prefix)) {
       return true;
    }
  }
     return false;
}

Reference

Stripe Card Builder


O
OhhhThatVarun

Try this for kotlin. Add Regex and add to the when statement.

private fun getCardType(number: String): String {

        val visa = Regex("^4[0-9]{12}(?:[0-9]{3})?$")
        val mastercard = Regex("^5[1-5][0-9]{14}$")
        val amx = Regex("^3[47][0-9]{13}$")

        return when {
            visa.matches(number) -> "Visa"
            mastercard.matches(number) -> "Mastercard"
            amx.matches(number) -> "American Express"
            else -> "Unknown"
        }
    }

G
Gajus

The regular expression rules that match the respective card vendors:

(4\d{12}(?:\d{3})?) for VISA.

(5[1-5]\d{14}) for MasterCard.

(3[47]\d{13}) for AMEX.

((?:5020|5038|6304|6579|6761)\d{12}(?:\d\d)?) for Maestro.

(3(?:0[0-5]|[68][0-9])[0-9]{11}) for Diners Club.

(6(?:011|5[0-9]{2})[0-9]{12}) for Discover.

(35[2-8][89]\d\d\d{10}) for JCB.


I think that regex for JCB is incorrect. All first four digits between 3528 and 3589 should be accepted, but 3570 is not, for example.
g
gaurav gupta
follow Luhn’s algorithm

 private  boolean validateCreditCardNumber(String str) {

        int[] ints = new int[str.length()];
        for (int i = 0; i < str.length(); i++) {
            ints[i] = Integer.parseInt(str.substring(i, i + 1));
        }
        for (int i = ints.length - 2; i >= 0; i = i - 2) {
            int j = ints[i];
            j = j * 2;
            if (j > 9) {
                j = j % 10 + 1;
            }
            ints[i] = j;
        }
        int sum = 0;
        for (int i = 0; i < ints.length; i++) {
            sum += ints[i];
        }
        if (sum % 10 == 0) {
           return true;
        } else {
            return false;
        }


    }

then call this method

Edittext mCreditCardNumberEt;

 mCreditCardNumberEt.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

             int cardcount=   s.toString().length();
                 if(cardcount>=16) {
                    boolean cardnumbervalid=   validateCreditCardNumber(s.toString());
                    if(cardnumbervalid) {
                        cardvalidtesting.setText("Valid Card");
                        cardvalidtesting.setTextColor(ContextCompat.getColor(context,R.color.green));
                    }
                    else {
                        cardvalidtesting.setText("Invalid Card");
                        cardvalidtesting.setTextColor(ContextCompat.getColor(context,R.color.red));
                    }
                }
               else if(cardcount>0 &&cardcount<16) {
                     cardvalidtesting.setText("Invalid Card");
                     cardvalidtesting.setTextColor(ContextCompat.getColor(context,R.color.red));
                }

                else {
                    cardvalidtesting.setText("");

                }


                }

            @Override
            public void afterTextChanged(Editable s) {

            }
        });