How to debug Azure Web App memory leaks?

Try using Kudu console.Go to https://[sitename].scm.azurewebsites.net/supportClick Analyze -> Dignostics -> Settings. Make sure Memory dumps is checkedAnd then Click Dignose Now.This will work only in Basic plan and above (Not available for free plan)After some time you will get the dumpOpen the downloaded file with Visual studio and select "Debug managed memory".You can then see the details.

Unfortunately the kudu support page has been deprecated. You can now find it under Diagnose and solve problems:

Once you've downloaded the dump files, open them in Visual Studio and click "Collect a memory dump" like the accepted answer from Grandhali suggested.

I see this thread is pretty old, but since I had the same problem and the azure portal changes a lot during the time I want to post a little update here.

This microsoft dev blog gives a fast overview about the topic: https://devblogs.microsoft.com/premier-developer/collect-and-automate-diagnostic-actions-with-azure-app-services/

I managed to do the memory leak analysis by navigating to my App Service in Azure portal, selecting Diagnose and solve problems and afterwards the Diagnostic Tools tile. Now you should see a Collect Memory Dump tile where you can create your memory dump by configuring a blob storage to save it to.

Afterwards I downloaded the dumps and used Visual Studio to analyze the issues.