How do I get client IP address in ASP.NET Core?

The API has been updated. Not sure when it changed but according to Damien Edwards in late December, you can now do this:

var remoteIpAddress = request.HttpContext.Connection.RemoteIpAddress;

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In project.json add a dependency to:

"Microsoft.AspNetCore.HttpOverrides": "2.2.0"

In Startup.cs, in the Configure() method add:

app.UseForwardedHeaders(new ForwardedHeadersOptions
{
    ForwardedHeaders = ForwardedHeaders.XForwardedFor |
    ForwardedHeaders.XForwardedProto
});  

And, of course:

using Microsoft.AspNetCore.HttpOverrides;

Then, I could get the ip by using:

Request.HttpContext.Connection.RemoteIpAddress

In my case, when debugging in VS I got always IpV6 localhost, but when deployed on an IIS I got always the remote IP.

Some useful links: How do I get client IP address in ASP.NET CORE? and RemoteIpAddress is always null

The ::1 is maybe because of:

Connections termination at IIS, which then forwards to Kestrel, the v.next web server, so connections to the web server are indeed from localhost. (https://stackoverflow.com/a/35442401/5326387)

Edit 12/2020: Thanks to SolidSnake: as of Dec 2020 the latest version is 2.2.0

Edit 06/2021: Thanks to Hakan Fıstık: In .NET 5 the namespace is Microsoft.AspNetCore.Builder

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Some fallback logic can be added to handle the presence of a Load Balancer.

Also, through inspection, the X-Forwarded-For header happens to be set anyway even without a Load Balancer (possibly because of additional Kestrel layer?):

public string GetRequestIP(bool tryUseXForwardHeader = true)
{
    string ip = null;

    // todo support new "Forwarded" header (2014) https://en.wikipedia.org/wiki/X-Forwarded-For

    // X-Forwarded-For (csv list):  Using the First entry in the list seems to work
    // for 99% of cases however it has been suggested that a better (although tedious)
    // approach might be to read each IP from right to left and use the first public IP.
    // http://stackoverflow.com/a/43554000/538763
    //
    if (tryUseXForwardHeader)
        ip = GetHeaderValueAs<string>("X-Forwarded-For").SplitCsv().FirstOrDefault();

    // RemoteIpAddress is always null in DNX RC1 Update1 (bug).
    if (ip.IsNullOrWhitespace() && _httpContextAccessor.HttpContext?.Connection?.RemoteIpAddress != null)
        ip = _httpContextAccessor.HttpContext.Connection.RemoteIpAddress.ToString();

    if (ip.IsNullOrWhitespace())
        ip = GetHeaderValueAs<string>("REMOTE_ADDR");

    // _httpContextAccessor.HttpContext?.Request?.Host this is the local host.

    if (ip.IsNullOrWhitespace())
        throw new Exception("Unable to determine caller's IP.");

    return ip;
}

public T GetHeaderValueAs<T>(string headerName)
{
    StringValues values;

    if (_httpContextAccessor.HttpContext?.Request?.Headers?.TryGetValue(headerName, out values) ?? false)
    {
        string rawValues = values.ToString();   // writes out as Csv when there are multiple.

        if (!rawValues.IsNullOrWhitespace())
            return (T)Convert.ChangeType(values.ToString(), typeof(T));
    }
    return default(T);
}

public static List<string> SplitCsv(this string csvList, bool nullOrWhitespaceInputReturnsNull = false)
{
    if (string.IsNullOrWhiteSpace(csvList))
        return nullOrWhitespaceInputReturnsNull ? null : new List<string>();

    return csvList
        .TrimEnd(',')
        .Split(',')
        .AsEnumerable<string>()
        .Select(s => s.Trim())
        .ToList();
}

public static bool IsNullOrWhitespace(this string s)
{
    return String.IsNullOrWhiteSpace(s);
}

Assumes _httpContextAccessor was provided through DI.

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You can use the IHttpConnectionFeature for getting this information.

var remoteIpAddress = httpContext.GetFeature<IHttpConnectionFeature>()?.RemoteIpAddress;

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In ASP.NET 2.1, In StartUp.cs Add This Services:

services.AddHttpContextAccessor();
services.TryAddSingleton<IActionContextAccessor, ActionContextAccessor>();

and then do 3 step:

Define a variable in your MVC controller private IHttpContextAccessor _accessor; DI into the controller's constructor public SomeController(IHttpContextAccessor accessor) { _accessor = accessor; } Retrieve the IP Address _accessor.HttpContext.Connection.RemoteIpAddress.ToString()

This is how it is done.

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I found that, some of you found that the IP address you get is :::1 or 0.0.0.1

This is the problem because of you try to get IP from your own machine, and the confusion of C# that try to return IPv6.

So, I implement the answer from @Johna (https://stackoverflow.com/a/41335701/812720) and @David (https://stackoverflow.com/a/8597351/812720), Thanks to them!

and here to solution:

add Microsoft.AspNetCore.HttpOverrides Package in your References (Dependencies/Packages) add this line in Startup.cs public void Configure(IApplicationBuilder app, IHostingEnvironment env) { // your current code // start code to add // to get ip address app.UseForwardedHeaders(new ForwardedHeadersOptions { ForwardedHeaders = ForwardedHeaders.XForwardedFor | ForwardedHeaders.XForwardedProto }); // end code to add } to get IPAddress, use this code in any of your Controller.cs IPAddress remoteIpAddress = Request.HttpContext.Connection.RemoteIpAddress; string result = ""; if (remoteIpAddress != null) { // If we got an IPV6 address, then we need to ask the network for the IPV4 address // This usually only happens when the browser is on the same machine as the server. if (remoteIpAddress.AddressFamily == System.Net.Sockets.AddressFamily.InterNetworkV6) { remoteIpAddress = System.Net.Dns.GetHostEntry(remoteIpAddress).AddressList .First(x => x.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork); } result = remoteIpAddress.ToString(); }

and now you can get IPv4 address from remoteIpAddress or result

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var remoteIpAddress = HttpContext.Features.Get<IHttpConnectionFeature>()?.RemoteIpAddress;

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This works for me (DotNetCore 2.1)

[HttpGet]
public string Get() 
{
    var remoteIpAddress = HttpContext.Connection.RemoteIpAddress;
    return remoteIpAddress.ToString();
}

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As of September 2021 - ASP.NET Core (5.x) MVC project allowed me to get the IP Address this way in my controller:

Request.HttpContext.Connection.RemoteIpAddress

Quite a bit more simple now than in the past, it seems.

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In my case, I have DotNet Core 2.2 Web App running on DigitalOcean with docker and nginx as reverse proxy. With this code in Startup.cs I can get the client IP

app.UseForwardedHeaders(new ForwardedHeadersOptions
        {
            ForwardedHeaders = ForwardedHeaders.All,
            RequireHeaderSymmetry = false,
            ForwardLimit = null,
            KnownNetworks = { new IPNetwork(IPAddress.Parse("::ffff:172.17.0.1"), 104) }
        });

::ffff:172.17.0.1 was the ip that I was getting before using

Request.HttpContext.Connection.RemoteIpAddress.ToString();

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In .NET 5 I use this to retrieve the client IP via a container on AWS fargate.

public static class HttpContextExtensions
{
    //https://gist.github.com/jjxtra/3b240b31a1ed3ad783a7dcdb6df12c36

    public static IPAddress GetRemoteIPAddress(this HttpContext context, bool allowForwarded = true)
    {
        if (allowForwarded)
        {
            string header = (context.Request.Headers["CF-Connecting-IP"].FirstOrDefault() ?? context.Request.Headers["X-Forwarded-For"].FirstOrDefault());
            if (IPAddress.TryParse(header, out IPAddress ip))
            {
                return ip;
            }
        }
        return context.Connection.RemoteIpAddress;
    }
}

You call it like this:

var ipFromExtensionMethod = HttpContext.GetRemoteIPAddress().ToString();

Source

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Running .NET core (3.1.4) on IIS behind a Load balancer did not work with other suggested solutions.

Manually reading the X-Forwarded-For header does. This code assumes this header contains one IP.

IPAddress ip;
var headers = Request.Headers.ToList();
if (headers.Exists((kvp) => kvp.Key == "X-Forwarded-For"))
{
    // when running behind a load balancer you can expect this header
    var header = headers.First((kvp) => kvp.Key == "X-Forwarded-For").Value.ToString();
    // in case the IP contains a port, remove ':' and everything after
    ip = IPAddress.Parse(header.Remove(header.IndexOf(':')));
}
else
{
    // this will always have a value (running locally in development won't have the header)
    ip = Request.HttpContext.Connection.RemoteIpAddress;
}

Thanks to @JawadAlShaikh and @BozoJoe for pointing out the IP can contain a port and the X-Forwarded-For can contain multiple IPs.

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First, in .Net Core 1.0 Add using Microsoft.AspNetCore.Http.Features; to the controller Then inside the relevant method:

var ip = HttpContext.Features.Get<IHttpConnectionFeature>()?.RemoteIpAddress?.ToString();

I read several other answers which failed to compile because it was using a lowercase httpContext, leading the VS to add using Microsoft.AspNetCore.Http, instead of the appropriate using, or with HttpContext (compiler is also mislead).

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Running ASP.NET Core 2.1 behind a Traefik reverse Proxy on Ubuntu, I need to set its gateway IP in KnownProxies after installing the official Microsoft.AspNetCore.HttpOverrides package

        var forwardedOptions = new ForwardedHeadersOptions {
            ForwardedHeaders = ForwardedHeaders.XForwardedFor,
        };
        forwardedOptions.KnownProxies.Add(IPAddress.Parse("192.168.3.1"));
        app.UseForwardedHeaders(forwardedOptions);

According to the documentation, this is required if the reverse proxy is not running on localhost. The docker-compose.yml of Traefik has assigned a static IP address:

networks:
  my-docker-network:
    ipv4_address: 192.168.3.2

Alternatively, it should be enough to make sure a known network is defined here to specify its gateway in .NET Core.

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As per the official documentation, if you are using Apache or Nginx integration, following code should be added to the Startup.ConfigureServices method.

// using Microsoft.AspNetCore.HttpOverrides;

    services.Configure<ForwardedHeadersOptions>(options =>
    {
        options.ForwardedHeaders = ForwardedHeaders.XForwardedFor | 
            ForwardedHeaders.XForwardedProto;
        // Only loopback proxies are allowed by default.
        // Clear that restriction because forwarders are enabled by explicit 
        // configuration.
        options.KnownNetworks.Clear();
        options.KnownProxies.Clear();
    });

and then on top of everything, in Configure method use

app.UseForwardedHeaders();

Further suppose in nginx conf file, inside a location, use

proxy_set_header   Host $host;
proxy_set_header   X-Real-IP $remote_addr;
proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header   X-Forwarded-Host $server_name;

Now the first entry in the X-Forwarded-For will be the real client IP.

IMPORTANT: If you want to secure the app and not allow an attacker inject X-Forwarded-For, Please read this answer.

Please see Forward the scheme for Linux and non-IIS reverse proxies, Configure Nginx and Dealing with invalid headers

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First Add

Microsoft.AspNetCore.Http
services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();

in ConfigureServices in Startup.cs Then Add the following code in your controller

   private IHttpContextAccessor _accessor;
    
  public LoginController(IHttpContextAccessor accessor)
            {
              _accessor = accessor;
            }

  public IEnumerable<string> Get()
        {
         var ip = _accessor.HttpContext?.Connection?.RemoteIpAddress?.ToString();
         return new string[] { ip, "value" };
        }

Hope this will work for you

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try this:

string remoteHost = $"{httpContext.Connection.RemoteIpAddress}:{httpContext.Connection.RemotePort}";

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You can also get both IP Address and the location using the api.db-ip.com web service.

The service is free, but it has a limitation: 1,000 requests per day.

public string GetRemoteIP()
{
    HttpClient client = new HttpClient();
    var result = client.GetStringAsync("https://api.db-ip.com/v2/free/self").Result;
    var ip = JsonSerializer.Deserialize<RemoteIPDto>(result.ToString()).IP;
    return ip;
}
public static string GetUserAddress()
{
      HttpClient client = new HttpClient();
      var result = client.GetStringAsync("https://api.db-ip.com/v2/free/self").Result;
      var location = result.ToString();
      return remoteAddress;
}

where RemoteIPDto class is

public class RemoteIPDto
{
    [JsonPropertyName("ipAddress")]
    public string IP { get; set; }
    [JsonPropertyName("continentCode")]
    public string ContinentCode { get; set; }
    [JsonPropertyName("continentName")]
    public string ContinentName { get; set; }
    [JsonPropertyName("countryCode")]
    public string CountryCode { get; set; }
    [JsonPropertyName("countryName")]
    public string CountryName { get; set; }
    [JsonPropertyName("city")]
    public string City { get; set; }
}

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From this link, there is a better solution.

In Startup.cs, we need to add service-

public void ConfigureServices(IServiceCollection services)
{
    ........
    services.AddHttpContextAccessor();
    ........
}

Then in any controller or any place, we need to use it via dependency injection like this-

private IHttpContextAccessor HttpContextAccessor { get; }

public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options, IWebHostEnvironment env, IHttpContextAccessor httpContextAccessor)
        : base(options)
{
    Environment = env;
    HttpContextAccessor = httpContextAccessor;
    //this.Database.EnsureCreated();
}

And then get IP like this-

IPAddress userIp = HttpContextAccessor.HttpContext.Connection.RemoteIpAddress;

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Short version of @crokusek's answer

public string GetUserIP(HttpRequest req)
{
    var ip = req.Headers["X-Forwarded-For"].FirstOrDefault();

    if (!string.IsNullOrWhiteSpace(ip)) ip = ip.Split(',')[0];

    if (string.IsNullOrWhiteSpace(ip)) ip = Convert.ToString(req.HttpContext.Connection.RemoteIpAddress);

    if (string.IsNullOrWhiteSpace(ip)) ip = req.Headers["REMOTE_ADDR"].FirstOrDefault();

    return ip;
}

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using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Http.Features;

public string GetClientIPAddress(HttpContext context)
    {
        string ip = string.Empty;
if (!string.IsNullOrEmpty(context.Request.Headers["X-Forwarded-For"]))
        {
            ip = context.Request.Headers["X-Forwarded-For"];
        }
        else
        {
            ip = context.Request.HttpContext.Features.Get<IHttpConnectionFeature>().RemoteIpAddress.ToString();
        }
        return ip;
    }

Where you want to get Ip address;

GetClientIPAddress(HttpContext);

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You can also get IP from an external service.

public string GetIP()
{
    HttpClient client = new HttpClient();
    var result = client.GetStringAsync("https://jsonip.com/").Result;
    var ip = JsonSerializer.Deserialize<RemoteIPDto>(result.ToString()).IP;
    return ip;
}

Where RemoteIPDto class is

public class RemoteIPDto
{
    [JsonPropertyName("ip")]
    public string IP { get; set; }
    [JsonPropertyName("geo-ip")]
    public string GeoIp { get; set; }
    [JsonPropertyName("API Help")]
    public string ApiHelp { get; set; }
}

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try this.

var host = Dns.GetHostEntry(Dns.GetHostName());
        foreach (var ip in host.AddressList)
        {
            if (ip.AddressFamily == AddressFamily.InterNetwork)
            {
                 ipAddress = ip.ToString();
            }
        }

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To get IP address and hostname in .NET Core, put the following code in the controller:

var addlist = Dns.GetHostEntry(Dns.GetHostName());
string GetHostName = addlist.HostName.ToString();
string GetIPV6 = addlist.AddressList[0].ToString();
string GetIPV4 = addlist.AddressList[1].ToString();

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