Debug add-ins in Office Online

You can build and debug add-ins on a computer that isn't running Windows or the Office desktop client—for example, if you're developing on a Mac. This article describes how to use Office Online to test and debug your add-ins.


To get started:

  • Get an Office 365 developer account if you don't already have one or have access to a SharePoint site.


    To sign up for a free Office 365 developer subscription, join our Office 365 Developer Program. See the Office 365 Developer Program documentation for step-by-step instructions about how to join the Office 365 Developer Program and sign up and configure your subscription.

  • Set up an add-in catalog on Office 365 (SharePoint Online). An add-in catalog is a dedicated site collection in SharePoint Online that hosts document libraries for Office Add-ins. If you have your own SharePoint site, you can set up an add-in catalog document library. For more information, see Publish task pane and content add-ins to an add-in catalog on SharePoint.

Debug your add-in from Excel Online or Word Online

To debug your add-in by using Office Online:

  1. Deploy your add-in to a server that supports SSL.


    We recommend that you use the Yeoman generator to create and host your add-in.

  2. In your add-in manifest file, update the SourceLocation element value to include an absolute, rather than a relative, URI. For example:

    <SourceLocation DefaultValue="https://localhost:44300/App/Home/Home.html" />
  3. Upload the manifest to the Office Add-ins library in the add-in catalog on SharePoint.

  4. Launch Excel Online or Word Online from the app launcher in Office 365, and open a new document.

  5. On the Insert tab, choose My Add-ins or Office Add-ins to insert your add-in and test it in the app.

  6. Use your favorite browser tool debugger to debug your add-in.

Potential issues

The following are some issues that you might encounter as you debug:

  • Some JavaScript errors that you see might originate from Office Online.

  • The browser might show an invalid certificate error that you will need to bypass.

  • If you set breakpoints in your code, Office Online might throw an error indicating that it is unable to save.

See also