API
HTTP Status Code Reference
A practical list of common HTTP status codes. Look up a code instantly with the FreeToolMate status lookup — explanations stay in your browser.
1xx — Informational
- 100 Continue — client may send the rest of the request body
- 101 Switching Protocols — server agrees to change protocols (for example WebSocket)
2xx — Success
- 200 OK — request succeeded
- 201 Created — resource created (typical for POST)
- 204 No Content — success with an empty body
3xx — Redirection
- 301 Moved Permanently — permanent redirect; update bookmarks and links
- 302 Found — temporary redirect
- 304 Not Modified — cached response is still valid
4xx — Client errors
- 400 Bad Request — malformed request or invalid payload
- 401 Unauthorized — authentication required or failed
- 403 Forbidden — authenticated but not allowed
- 404 Not Found — resource does not exist
- 409 Conflict — state conflict (for example duplicate create)
- 422 Unprocessable Entity — validation failed on a well-formed request
- 429 Too Many Requests — rate limited
5xx — Server errors
- 500 Internal Server Error — unexpected server failure
- 502 Bad Gateway — upstream proxy got an invalid response
- 503 Service Unavailable — overloaded or down for maintenance
- 504 Gateway Timeout — upstream did not respond in time
Try it
Open the HTTP Status Lookup tool to search by code or phrase. Pair it with the HTTP Headers Viewer and cURL Generator when debugging APIs.