How to specify the port an ASP.NET Core application is hosted on?

When using WebHostBuilder in a Main entry-point, how can I specify the port it binds to?

By default it uses 5000.

Note that this question is specific to the new ASP.NET Core API (currently in 1.0.0-RC2).

In ASP.NET Core 3.1, there are four main ways to specify a custom port:

• Using command line arguments, by starting your .NET application with --urls=[url]:

  dotnet run --urls=http://localhost:5001/
  

• Using appsettings.json, by adding a Urls node:

  {
     "Urls": "http://localhost:5001"
  }
  

• Using environment variables, with ASPNETCORE_URLS=http://localhost:5001/.

• Using UseUrls(), if you prefer doing it programmatically:

  public static class Program
  {
       public static void Main(string[] args) =>
           CreateHostBuilder(args).Build().Run();
  
       public static IHostBuilder CreateHostBuilder(string[] args) =>
           Host.CreateDefaultBuilder(args)
               .ConfigureWebHostDefaults(builder =>
               {
                   builder.UseStartup<Startup>();
                   builder.UseUrls("http://localhost:5001/");
               });
  }
  

Or, if you're still using the web host builder instead of the generic host builder:

public class Program
{
    public static void Main(string[] args) =>
        new WebHostBuilder()
            .UseKestrel()
            .UseContentRoot(Directory.GetCurrentDirectory())
            .UseIISIntegration()
            .UseStartup<Startup>()
            .UseUrls("http://localhost:5001/")
            .Build()
            .Run();
}