อธิบาย 405 Method Not Allowed

A 405 Method Not Allowed response means the URL exists, but the verb you used is not permitted on it.

Do not confuse the two. A 404 means the path was not found, while a 405 means the path is real but rejects that verb.

If a route lists only POST and a client sends GET, Flask returns 405 automatically before your view ever runs.

A well-formed 405 includes an Allow header listing the verbs the route does accept, so clients learn what to use instead.

Codes in the 4xx range blame the request, not the server. A 405 says the client picked the wrong method for that endpoint.

Submitting a form whose route forgot to allow POST is the classic trigger. Add POST to the methods list to fix it.

Typing a URL sends a GET. If that route only allows POST, the browser shows a 405 instead of your page.

Give clients a friendlier reply by registering an errorhandler for 405 that returns your own message or JSON.

For an API, a 405 should still speak JSON. A handler keeps your error shape consistent with every other response.

When debugging, inspect the response's Allow header. It tells you exactly which verbs the route was declared to accept.

The real fix is almost always in the methods list. Add the verb you need rather than working around the 405 elsewhere.

Tell 405 apart from its neighbor.

A 405 means a valid URL with a disallowed verb, unlike a 404. Read the Allow header and fix it by updating the methods list. Well done! 🎯