What does HTTP 431 mean?
The headers are too large for the server to process.
Common causes and when you see it
Oversized cookies or authorization headers.
How to fix or handle it
Clear cookies or reduce header size.
Test it yourself
Send a request with the online API tester, inspect the response with the HTTP header checker, or host an endpoint that returns 431 with the mock API generator to see how your app reacts.
HTTP 431 questions
The headers are too large for the server to process.
Oversized cookies or authorization headers.
Clear cookies or reduce header size.