HTTP Status Codes & REST API Response Codes Cheat Sheet

The complete HTTP status code reference guide for web developers and API designers. Covers 1xx, 2xx, 3xx, 4xx, and 5xx responses.

2xx Success Responses

Standard response for successful HTTP GET, PUT, or POST requests200 OK

Resource was successfully created (standard for POST resource creation)201 Created

Request succeeded but server sends no response body (common for DELETE)204 No Content

3xx Redirection Responses

Resource permanently moved to new URL (passes SEO link equity)301 Moved Permanently

Resource temporarily located at a different URL302 Found (Temporary)

Client cached version is still fresh and valid (ETag / If-Modified-Since)304 Not Modified

4xx Client Errors

Server cannot process request due to client error (invalid JSON / malformed syntax)400 Bad Request

Authentication is required and has either failed or not yet been provided401 Unauthorized

Client identity is known, but server refuses authorization to access resource403 Forbidden

Server cannot find the requested URL resource404 Not Found

Semantic validation failed (correct JSON syntax, but invalid field values)422 Unprocessable Entity

Client has sent too many requests in given timeframe (Rate Limited)429 Too Many Requests

5xx Server Errors

Generic unhandled server crash or runtime exception500 Internal Server Error

Proxy or edge gateway received an invalid response from upstream server502 Bad Gateway

Server is currently unable to handle request due to overload or maintenance503 Service Unavailable

Upstream server failed to respond to proxy within configured timeout limit504 Gateway Timeout

Frequently Asked Questions

• What is the exact difference between 401 Unauthorized and 403 Forbidden?

401 means "Unauthenticated": the user is not logged in or token is invalid. 403 means "Forbidden": the user is logged in, but their account or role does not have permission to access that resource.