How to change base url of Swagger in ASP.NET core

By default when you enable swagger in ASP.NET Core project it's available on url:

http://localhost:<random_port>/swagger/ui

I would like to use a different base url instead of /swagger/ui. How/where can i configure that?

I found that for older versions you can configure the RootUrl but there aren't similiar method in ASP.NET Core:

.EnableSwagger(c =>
{
    c.RootUrl(req => myCustomBasePath);
});

The new swagger version provides you with a property called RoutePrefix.

app.UseSwaggerUI(c =>
{
    c.SwaggerEndpoint("/swagger/v1/swagger.json", "My API V1");
    c.RoutePrefix = "docs";
});

Should work for .net core

For ASP.NET Core 2 (and using Swashbuckle.AspNetCore.Swagger -Version 4.0.1), a couple things can be done for a full configuration of changing the default swagger UI base URL.

If you want to add "mycoolapi" to the beginning of your default swagger UI URL, like this: http://<server>/mycoolapi/swagger, then do the following:

In your Startup.cs Configure method:

	app.UseSwagger(c =>
	{
		c.RouteTemplate = "mycoolapi/swagger/{documentname}/swagger.json";
	});


	app.UseSwaggerUI(c =>
	{
		c.SwaggerEndpoint("/mycoolapi/swagger/v1/swagger.json", "My Cool API V1");
		c.RoutePrefix = "mycoolapi/swagger";
	});

Then, if you currently have your launchSettings to launch browser at swagger UI upon startup (for development purposes), update your launchSettings.json file profiles section similarly:

  "profiles": {
    "IIS Express": {
      "commandName": "IISExpress",
      "launchBrowser": true,
      "launchUrl": "mycoolapi/swagger",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    },
    "MyProject.Web": {
      "commandName": "Project",
      "launchBrowser": true,
      "launchUrl": "mycoolapi/swagger",
      "applicationUrl": "https://localhost:5001;http://localhost:5000",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    }
  }

You can do this as well in Config

app.UseSwaggerUI(c =>
            {
                c.RoutePrefix = string.Empty;
                c.SwaggerEndpoint("/swagger/v1/swagger.json", "MY API");
            });

Other answers didn't work for me in .NET 5. Here is how I added 'docs' to the route

app.UseSwagger(c => c.RouteTemplate = "/swagger/docs/{documentName}/swagger.json");
app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/docs/v2/swagger.json", "My API"));

1. Open the launchSettings.json file.
2. Under the "profiles" node depending on your setup you should have one or more profiles. In may case I had "IIS Express" and another with named with my project name (e.g WebApplication1 ), now changing the launchUrl entry to "launchUrl": "swagger" solved my problem.
3. If this does not work and you have other profiles do the same and test.

I had to dig through the original docs because all the above solutions did not work. This code in Startup.cs is what is working for me:

app.UseSwagger();
app.UseSwaggerUI(c => {
    c.SwaggerEndpoint($"./v1/swagger.json", "SapWeb v1");
});

My site is a subsite in IIS. So, at first, I had to set PathBase:

app.UsePathBase($"{pathbase}");

The UseSwaggerUi() extension method to enable the middleware in the Configure method of the StartUp class takes two variables. A baseRoute which is on swagger/ui by default, and swaggerUrl which is on swagger/v1/swagger.json by default. Simply provide a different baseRoute.

//Swagger will be available under '/api' url
app.UseSwaggerUi("api");

If people would like to learn more about configuring Swagger for ASP.NET Core, I've written a blogpost to get started: https://dannyvanderkraan.wordpress.com/2016/09/09/asp-net-core-1-0-web-api-automatic-documentation-with-swagger-and-swashbuckle/