How to check .net runtime version in Azure App Service

Using the Azure Portal

1. Sign in to the Azure portal.
2. Navigate to your App Service and select it.
3. In the left navigation menu, under Settings, select Configuration.
4. Select the General settings tab.
5. In the Stack settings section, you will see the Runtime stack and the specific .NET version being used. 

Using the Kudu Console (Advanced Tools)

The Kudu console provides direct access to the underlying environment and installed runtimes. 

• 1. In the Azure portal, navigate to your App Service.
  2. Under Development Tools, select Advanced Tools, then select Go.
  3. In the Kudu services window, select Debug console and choose either CMD or PowerShell.
  4. Run the appropriate command in the console:
     • For .NET Core and .NET 5+, run dotnet --list-runtimes or dotnet --info to see all installed versions.