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Regex for password must contain at least eight characters, at least one number and both lower and uppercase letters and special characters

I want a regular expression to check that:

A password contains at least eight characters, including at least one number and includes both lower and uppercase letters and special characters, for example #, ?, !.

It cannot be your old password or contain your username, "password", or "websitename"

And here is my validation expression which is for eight characters including one uppercase letter, one lowercase letter, and one number or special character.

(?=^.{8,}$)((?=.*\d)|(?=.*\W+))(?![.\n])(?=.*[A-Z])(?=.*[a-z]).*$"

How can I write it for a password must be eight characters including one uppercase letter, one special character and alphanumeric characters?


W
Wiktor Stribiżew

Minimum eight characters, at least one letter and one number:

"^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$"

Minimum eight characters, at least one letter, one number and one special character:

"^(?=.*[A-Za-z])(?=.*\d)(?=.*[@$!%*#?&])[A-Za-z\d@$!%*#?&]{8,}$"

Minimum eight characters, at least one uppercase letter, one lowercase letter and one number:

"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[a-zA-Z\d]{8,}$"

Minimum eight characters, at least one uppercase letter, one lowercase letter, one number and one special character:

"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{8,}$"

Minimum eight and maximum 10 characters, at least one uppercase letter, one lowercase letter, one number and one special character:

"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{8,10}$"

"^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$" does not allow symbols as one of the 8 characters
I found the following allowed for all characters (special & punctuation), without making them mandatory: "^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[a-zA-Z\d\w\W]{8,}$"
@Gavin With this regex the string "DdBxgyZv2FBaa" is valid but should not detected as valid, because there is no special character.
a
anubhava

You may use this regex with multiple lookahead assertions (conditions):

^(?=.*?[A-Z])(?=.*?[a-z])(?=.*?[0-9])(?=.*?[#?!@$%^&*-]).{8,}$

This regex will enforce these rules:

At least one upper case English letter, (?=.*?[A-Z])

At least one lower case English letter, (?=.*?[a-z])

At least one digit, (?=.*?[0-9])

At least one special character, (?=.*?[#?!@$%^&*-])

Minimum eight in length .{8,} (with the anchors)


much detailed answer for regex
P
Peter Mortensen

Regular expressions don't have an AND operator, so it's pretty hard to write a regex that matches valid passwords, when validity is defined by something AND something else AND something else...

But, regular expressions do have an OR operator, so just apply DeMorgan's theorem, and write a regex that matches invalid passwords:

Anything with less than eight characters OR anything with no numbers OR anything with no uppercase OR or anything with no lowercase OR anything with no special characters.

So:

^(.{0,7}|[^0-9]*|[^A-Z]*|[^a-z]*|[a-zA-Z0-9]*)$

If anything matches that, then it's an invalid password.


This is one of the better answers. Other answers don't include special characters like "(" or ")". Great solution!
P
Peter Mortensen

Just a small improvement for @anubhava's answer: Since special character are limited to the ones in the keyboard, use this for any special character:

^(?=.*?[A-Z])(?=(.*[a-z]){1,})(?=(.*[\d]){1,})(?=(.*[\W]){1,})(?!.*\s).{8,}$

This regex will enforce these rules:

At least one upper case English letter

At least one lower case English letter

At least one digit

At least one special character

Minimum eight in length


In the JavaScript flavor, \W matches only ASCII characters. So you haven't changed that, and now you have to filter out whitespace characters. Furthermore, all the parentheses and {1,} quantifiers you added are pure noise, and removing the non-greedy (?) operators was pointless. There is no improvement here.
To consider the underscore a special character as well and some further other improvements, try eg: ^(?=[^A-Z\s]*[A-Z])(?=[^a-z\s]*[a-z])(?=[^\d\s]*\d)(?=\w*[\W_])\S{8,}$
H
HK boy

Use the following Regex to satisfy the below conditions:

Conditions:

Min 1 uppercase letter. Min 1 lowercase letter. Min 1 special character. Min 1 number. Min 8 characters. Max 30 characters.

Regex:

/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[#$@!%&*?])[A-Za-z\d#$@!%&*?]{8,30}$/

In which way is your answer better than the the other answers written years ago?
@JoshYates1980 can you please mention the "Special Character" for which the regex failed for you. Let me verify with that and update it accordingly. But as far I know it works with all as per the mandate condition of 1 special character. Awaiting for you response....
@SHASHANKHONRAO I updated the expression to: ^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[$@$!%*?&+~|{}:;<>/])[A-Za-z\d$@$!%*?&+~|{}:;<>/]{8,15} which will include the following Nonalphanumeric characters: (@$!%*?&+~`|{}:;<>/)
s
scniro

I had some difficulty following the most popular answer for my circumstances. For example, my validation was failing with characters such as ; or [. I was not interested in white-listing my special characters, so I instead leveraged [^\w\s] as a test - simply put - match non word characters (including numeric) and non white space characters. To summarize, here is what worked for me...

at least 8 characters

at least 1 numeric character

at least 1 lowercase letter

at least 1 uppercase letter

at least 1 special character

/^(?=.*?[A-Z])(?=.*?[a-z])(?=.*?[0-9])(?=.*?[^\w\s]).{8,}$/

JSFiddle Link - simple demo covering various cases


Nice one. but have found one issue that your regular expression will not accept _(underscore) as a special character :( .
I really like this answer except that it can't accept underscores. All I did was replace (?=.*?[^\w\s]) with (?=.*?([^\w\s]|[_])) to add support for underscores and it works great now. Also @Dinish.net the system I use trims the whitespace out of the password string when we get it, so using vanilla JS String.prototype.trim() method would work well if you want to use this answer.
S
SamWhan

A more "generic" version(?), allowing none English letters as special characters.

^(?=\S*[a-z])(?=\S*[A-Z])(?=\S*\d)(?=\S*[^\w\s])\S{8,}$

var pwdList = [ '@@V4-\3Z`zTzM{>k', '12qw!"QW12', '123qweASD!"#', '1qA!"#$%&', 'Günther32', '123456789', 'qweASD123', 'qweqQWEQWEqw', '12qwAS!' ], re = /^(?=\S*[a-z])(?=\S*[A-Z])(?=\S*\d)(?=\S*[^\w\s])\S{8,}$/; pwdList.forEach(function (pw) { document.write('' + pw + '
'); });


d
deathwombat

I would reply to Peter Mortensen, but I don't have enough reputation.

His expressions are perfect for each of the specified minimum requirements. The problem with his expressions that don't require special characters is that they also don't ALLOW special characters, so they also enforce maximum requirements, which I don't believe the OP requested. Normally you want to allow your users to make their password as strong as they want; why restrict strong passwords?

So, his "minimum eight characters, at least one letter and one number" expression:

^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$

achieves the minimum requirement, but the remaining characters can only be letter and numbers. To allow (but not require) special characters, you should use something like:

^(?=.*[A-Za-z])(?=.*\d).{8,}$ to allow any characters

or

^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d$@$!%*#?&]{8,}$ to allow specific special characters

Likewise, "minimum eight characters, at least one uppercase letter, one lowercase letter and one number:"

^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[a-zA-Z\d]{8,}$

meets that minimum requirement, but only allows letters and numbers. Use:

^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{8,}$ to allow any characters

or

^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[A-Za-z\d$@$!%*?&]{8,} to allow specific special characters.


P
Peter Mortensen

Import the JavaScript file jquery.validate.min.js.

You can use this method:

$.validator.addMethod("pwcheck", function (value) {
    return /[\@\#\$\%\^\&\*\(\)\_\+\!]/.test(value) && /[a-z]/.test(value) && /[0-9]/.test(value) && /[A-Z]/.test(value)
});

At least one upper case English letter At least one lower case English letter At least one digit At least one special character


S
Sazzad

For standard password requirements I found this to be useful:

At least 1 alphabet

At least 1 digit

Contains no space

Optional special characters e.g. @$!%*#?&^_-

Minimum 8 characters long /^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d@$!%*#?&^_-]{8,}$/

You can also set the upper limit for example {8,32} up to 32 characters long.


P
Peter Mortensen

Try this one:

Minimum six characters At least one uppercase character At least one lowercase character At least one special character

Expression:

"/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[$@$!%*?&.])[A-Za-z\d$@$!%*?&.]{6, 20}/"

Optional Special Characters:

At least one special character At least one number Special characters are optional Minimum six characters and maximum 16 characters

Expression:

"/^(?=.*\d)(?=.*[a-zA-Z]).{6,20}$/"

If the min and max condition is not required then remove .{6, 16}

6 is minimum character limit

20 is maximum character limit

?= means match expression


D
Dana

This worked for me:

^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[@$!%*?&])([a-zA-Z0-9@$!%*?&]{8,})$

At least 8 characters long;

One lowercase, one uppercase, one number and one special character;

No whitespaces.


yes its getting false with white spaces
H
Heikki Salokanto

Not directly answering the question, but does it really have to be a regex?

I used to do lots of Perl, and got used to solving problems with regexes. However, when they get more complicated with all the look-aheads and other quirks, you need to write dozens of unit tests to kill all those little bugs.

Furthermore, a regex is typically a few times slower than an imperative or a functional solution.

For example, the following (not very FP) Scala function solves the original question about three times faster than the regex of the most popular answer. What it does is also so clear that you don't need a unit test at all:

def validatePassword(password: String): Boolean = {
  if (password.length < 8)
    return false

  var lower = false
  var upper = false
  var numbers = false
  var special = false

  password.foreach { c =>
    if (c.isDigit)       numbers = true
    else if (c.isLower)  lower = true
    else if (c.isUpper)  upper = true
    else                 special = true
  }

  lower && upper && numbers && special
}

E
Emerson Joel Rojas Soliz

What about considering the following regex solution:

^(?=.*[\w])(?=.*[\W])[\w\W]{8,}$

Which validates the following:

At least one lowercase At least one uppercase At least one digit At least one special character At least it should have 8 characters long.

Check it out working at the following link https://regex101.com/r/qPmC06/4/


Your suggested regex and the one under the regex101 link varies. Shouldn't it be ^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[\W\_])[A-Za-z\d\W\_]{8,}$?
S
Steve Johnson

For a more strict validation where the following is required:

At least One Upper Case Character At least one Lower Case character At least one digit At least one symbol/special character @$!%*#?&^_- Minimum 8 characters/digits

Regex:

/(?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@$!%*#?&^_-]).{8,}/

I hope it helps someone with a more stringent.


M
Milan Paudyal
^(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9])(?=.*[!@#$%^&*()_+,.\\\/;':"-]).{8,}$
    

T
The fourth bird

Another option is to make use of contrast in the lookahead assertions using a negated character class, optionally matching any character except that is listed before matching the character that should be matched.

^(?=[^A-Z\n]*[A-Z])(?=[^a-z\n]*[a-z])(?=[^0-9\n]*[0-9])(?=[^#?!@$%^&*\n-]*[#?!@$%^&*-]).{8,}$

See a regex demo

In parts, the pattern matches:

^ Start of string

(?=[^A-Z\n]*[A-Z]) Positive lookahead, assert 0+ times any char except A-Z or a newline. Then match a char A-Z

(?=[^a-z\n]*[a-z]) The same approach for a char a-z

(?=[^0-9\n]*[0-9]) The same approach for a digit 0-9

(?=[^#?!@$%^&*\n-]*[#?!@$%^&*-]) The same approach for a char that you would consider special

.{8,} Match 8 or more times any character except a newline

$ End of string

Notes

A dot can also match a space. If you do not want to allow matching a space, then .{8,} can be changed to \S{8,} to match 8 or more non whitespace characters

Using either . or \S can match more characters than are specified in the lookahead assertions. If you only want to match the characters that are used in the assertions, you can change .{8,} to match only the allowed characters [#?!@$%^&*A-Za-z0-9-]{8,} using a character class

const regex = /^(?=[^A-Z\n]*[A-Z])(?=[^a-z\n]*[a-z])(?=[^0-9\n]*[0-9])(?=[^#?!@$%^&*\n-]*[#?!@$%^&*-]).{8,}$/; [ "abcA1#!A", "#!asdfSFD1;", "# a f F1 ;", "1111111111", "aaaaaaaa", "11111111", "AAAAAAAA", "########", "aA1#" ].forEach(s => console.log(regex.test(s) ? `Match --> ${s}` : `No match --> ${s}`) );


H
Hasan Tezcan
/^(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9]).*$/

this the simple way to use it while validate atleast 1 uppercase 1 lowercase and 1 number

and this is the example while I use in express validation

check('password')
    .notEmpty()
    .withMessage('Password cannot be null')
    .bail()
    .isLength({ min: 6 })
    .withMessage('Password must be at least 6 characters')
    .bail()
    .matches(/^(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9]).*$/)
    .withMessage(
      'Must have atleast 1 uppercase, 1 lowercase letter and 1 number'
    ),

M
MiKr13

Testing this one in 2020:

^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{8,}$

Verify yourself

const regex = /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{8,}$/; const str = `some12*Nuts`; let m; if ((m = regex.exec(str)) !== null) { // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }


S
Sadia Younas

Must contain at least 1 number, 1 uppercase, 1 lowercase letter and at least 8 or more characters: https://www.w3schools.com/howto/howto_js_password_validation.asp

pattern="(?=.*\d)(?=.*[a-z])(?=.*[A-Z]).{8,}"

R
Rasaf Ibrahim

✅ The following 4 regex patterns can help you to write almost any password validation

Pattern 1:

Password must contain one digit from 1 to 9, one lowercase letter, one uppercase letter, one special character, no space, and it must be 8-16 characters long.

/^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*\W)(?!.* ).{8,16}$/

Explanation:

(?=.*[0-9]) means that the password must contain a single digit from 1 to 9.

(?=.*[a-z]) means that the password must contain one lowercase letter.

(?=.*[A-Z]) means that the password must contain one uppercase letter.

(?=.*\W) means that the password must contain one special character.

.{8,16} means that the password must be 8-16 characters long. We must use this at the end of the regex, just before the $ symbol.

What are ^ and $:

^ indicates the beginning of the string. $ indicates the end of the string.

If we don't use these ^ & $, the regex will not be able to determine the maximum length of the password. In the above example, we have a condition that the password can't be longer than 16 characters, to make that condition work, we have used these ^ & $

Remove maximum length restriction:

Instead of .{8,16}, if we used .{8,}, it would mean that the password must be at least 8 characters long. So, there will not be any condition for checking the maximum length of the password.

Don't accept any number(digit):

Instead of (?=.*[0-9]), if we used (?!.*[0-9]), it would mean that the password must not contain any digit from 1-9 (Difference with the (?=.*[0-9]) is the use of ! instead of =)

Don't accept any spcecial character:

Instead of (?=.*\W), if we used (?!.*\W), it would mean that the password must not contain any special characters (The difference with the (?=.*\W) is the use of ! instead of =)

Alternative Syntax for number(digit):

Instead of (?=.*[0-9]), we could have used (?=.*\d). (?=.*\d) also means that the password must contain a single digit from 1 to 9.

Pattern 2:

Password must contain one digit from 1 to 9, one lowercase letter, one uppercase letter, one underscore but no other special character, no space and it must be 8-16 characters long.

/^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*_)(?!.*\W)(?!.* ).{8,16}$/

Difference with the Pattern 1

Here, we have used (?=.*_) which wasn't on the Pattern 1.

(?=.*_)(?!.*\W) means that the password must contain an underscore but can not contain any other special character.

Pattern 3:

Password must contain one digit from 1 to 9, one lowercase letter, one uppercase letter, one underscore, no space and it must be 8-16 characters long. Usage of any other special character other than underscore is optional.

/^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*_)(?!.* ).{8,16}$/

Difference with the Pattern 2

Here, we have not used (?!.*\W) what was on the Pattern 2.

But it still has the (?=.*_)

By just removing the (?!.*\W), special characters have become optional. Now, one underscore is required but any other special character can be used or not as it's optional.

Pattern 4:

Password must contain one digit from 1 to 9, one lowercase letter, one uppercase letter, and one underscore, and it must be 8-16 characters long. Usage of any other special character and usage of space is optional.

/^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z]).{8,16}$/

Difference with the Pattern 3

Here, we have not used (?=.*_) & (?!.* ) which was on the Pattern 3.

By removing (?=.*_), it's no longer mandatory to pass one underscore. Now, passing special characters is optional.

By removing the (?!.* ), usage of space has become optional too.


P
Peter Mortensen

According to your need this pattern should work just fine. Try this,

^(?=(.*\d){1})(.*\S)(?=.*[a-zA-Z\S])[0-9a-zA-Z\S]{8,}

Just create a string variable, assign the pattern, and create a boolean method which returns true if the pattern is correct, else false.

Sample:

String pattern = "^(?=(.*\d){1})(.*\S)(?=.*[a-zA-Z\S])[0-9a-zA-Z\S]{8,}";
String password_string = "Type the password here"

private boolean isValidPassword(String password_string) {
    return password_string.matches(Constants.passwordPattern);
}

S
SONewbiee

@ClasG has already suggested:

^(?=\S*[a-z])(?=\S*[A-Z])(?=\S*\d)(?=\S*[^\w\s])\S{8,}$

but it does not accept _(underscore) as a special character (eg. Aa12345_).

An improved one is:

^(?=\S*[a-z])(?=\S*[A-Z])(?=\S*\d)(?=\S*([^\w\s]|[_]))\S{8,}$

S
Stefano

I've found many problems here, so I made my own.

Here it is in all it's glory, with tests:

^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*([^a-zA-Z\d\s])).{9,}$

https://regex101.com/r/DCRR65/4/tests

Things to look out for:

doesn't use \w because that includes _, which I'm testing for. I've had lots of troubles matching symbols, without matching the end of the line. Doesn't specify symbols specifically, this is also because different locales may have different symbols on their keyboards that they may want to use.


M
Mohideen bin Mohammed

Demo:

function password_check() { pass = document.getElementById("password").value; console.log(pass); regex = /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&])[A-Za-z\d@$!%*?&]{8,}$/; if (regex.exec(pass) == null) { alert('invalid password!') } else { console.log("valid"); } }


M
Masoud
var strongRegex = new RegExp("^(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[!@#\$%\^&\*])(?=.{8,})");
var mediumRegex = new RegExp("^(((?=.*[a-z])(?=.*[A-Z]))|((?=.*[a-z])(?=.*[0-9]))|((?=.*[A-Z])(?=.*[0-9])))(?=.{6,})");

Best For javascript


What are the conditions of these regexs?
I think your mediumRegex variable is checking for at least 6 characters, instead of 8
M
Mosia Thabo

Keep it simple stupid:

This should do the trick for you, always.

Regex: ^(.{0,7}|[^a-z]{1,}|[^A-Z]{1,}|[^\d]{1,}|[^\W]{1,})$|[\s]

If your password matches the regex above, it is invalid.

If there's no match, your password is valid and contains has at least 8 characters, one upper case letter, one lower case letter and one symbol or special character. And it also contains no spaces, tabs or line breaks.

Breakdown of Regex

.{0,7} - matches if password has between 0 to 7 characters. [^a-z]{1,} - matches if no lower case is found [^A-Z]{1,} - matches if no upper case is found [^\d]{1,} - matches if no number (between [0-9]) is found [\s] - matches if a white space, tab or line break is found.

With this approach there's no limit or restriction in terms of symbols allowed. If you want to limit to few symbols allowable, just change [^\W] with [^YourSymbols].


M
Mike G
(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%^&+-]).{6}

for more detail please check knowledge-hubs.blogspot.in/2015/11/…
S
Samrat Saha

Use the following Regex to satisfy the below conditions:

Conditions: 1] Min 1 special character.
            2] Min 1 number.
            3] Min 8 characters or More

Regex: ^(?=.*\d)(?=.*[#$@!%&*?])[A-Za-z\d#$@!%&*?]{8,}$ Can Test Online: https://regex101.com


V
Vidya

Just we can do this by using HTML5.

Use below code in pattern attribute,

pattern="(?=^.{8,}$)((?=.*\d)(?=.*\W+))(?![.\n])(?=.*[A-Z])(?=.*[a-z]).*$"

It will work perfectly.