A list of all the official documentation provided by the push services about the HTTP status codes and errors that can be returned. When an application sends a notification to a browser push service, it should check the status code returned and take appropriate actions.
A push service provides a response for each push notification request. You need to inspect each HTTP response to see how the push service handled your push request.
The HTTP status code indicates if the request succeeds (e.g. 200, 201). If the request fails, the status code identifies the type of error (see also this related post). Sometimes a custom status code name or a response body may provide additional information about the error.
Here's the official documentation for all the major browsers:
You can also read the Web Push standard (RFC8030) for more information about the HTTP status codes.
Finally if a status code is not described in the documentation of the push service or in the standard, then you can assume the normal meaning for that status code, as defined in the HTTP standard (see the HTTP status codes on MDN).
Note: if you are using Pushpad for sending web push notifications from your website, then all the HTTP status codes and errors are managed automatically by our service. You don't need to do anything. Pushpad takes appropriate actions for each status code, including retries, removal of expired or invalid subscriptions and much more. It also generates simple reports about the delivery status in the dashboard.