4xx Client Error
405 Method Not Allowed
The URL exists, but not for the HTTP method you used.
What causes it
- POSTing to a route that only defines GET.
- A trailing-slash redirect turning a POST into a GET, which then 405s.
- A static host that only serves GET and HEAD receiving a POST.
How to fix it
- The response must include an `Allow` header listing the methods that are supported. Read it — it tells you exactly what to change.
- Check for a redirect immediately before the failing request; that is the usual cause when the same call works in Postman.
At a glance
- Class
- 4xx Client Error
- Reference
- RFC 9110 §15.5.6
- Standardised
- Yes
- Retry the request?
- No — fix the request
Other 4xx client error codes
- 400 Bad Request
- 401 Unauthorized
- 402 Payment Required
- 403 Forbidden
- 404 Not Found
- 406 Not Acceptable
- 407 Proxy Authentication Required
- 408 Request Timeout
- 409 Conflict
- 410 Gone
- 411 Length Required
- 412 Precondition Failed
- 413 Content Too Large
- 414 URI Too Long
- 415 Unsupported Media Type
- 416 Range Not Satisfiable
- 417 Expectation Failed
- 418 I'm a teapot
- 421 Misdirected Request
- 422 Unprocessable Content
- 423 Locked
- 424 Failed Dependency
- 425 Too Early
- 426 Upgrade Required
- 428 Precondition Required
- 429 Too Many Requests
- 431 Request Header Fields Too Large
- 451 Unavailable For Legal Reasons
- 499 Client Closed Request