HTTP Status Codes Explorer & RFC Guide

Initial part of a request received, client should continue with request payload.

Server agrees to switch protocols (e.g. upgrading HTTP connection to WebSockets).

Allows returning preliminary headers (e.g. Link preloads) while the server prepares final response.

Request succeeded and led to creation of a new resource (typically POST/PUT).

Request accepted for async processing, but processing has not completed yet (e.g. batch queue).

Request successfully processed, but returns no response body (common for DELETE and PUT).

Used for byte-range serving (e.g. video streaming or paused file resume downloads).

Target resource has been assigned a new permanent URI. Search engines pass SEO link equity.

Target resource resides temporarily under a different URI. SEO link juice is preserved.

Resource has not changed since the version specified by If-Modified-Since or If-None-Match.

Temporary redirect that guarantees the HTTP method (POST, PUT) will NOT be changed to GET.

Permanent redirect that guarantees the HTTP method (POST, PUT) will NOT be changed to GET.

Server cannot process the request due to malformed syntax, invalid JSON, or validation failure.

Authentication is required and has failed or has not been provided (missing/expired token).

Server understood request and caller is authenticated, but caller lacks necessary permissions.

Target resource does not exist on the server or server wishes to obscure its existence.

Request method (e.g. POST) is not supported for this endpoint URL.

Server did not receive a complete request message within the time it was prepared to wait.

Request could not be processed because of conflict in current state of resource (e.g. duplicate key or optimistic lock).

Request entity is larger than the server is willing or able to process (e.g. body exceeds 50MB).

Specified in April Fools' RFC 2324 (HTCPCP). Server refuses to brew coffee because it is a teapot.

Server understands content type and syntax, but was unable to process contained instructions (semantic errors).

User has sent too many requests in a given amount of time ('rate limiting').

Server encountered an unexpected condition that prevented it from fulfilling request (unhandled exception).

Server does not support functionality required to fulfill request (e.g. unknown HTTP verb).

Server, while acting as a gateway or proxy, received an invalid response from inbound upstream server.

Server is currently unable to handle request due to temporary overloading or maintenance.

Gateway or proxy did not receive a timely response from upstream server (e.g. NGINX timeout after 60s).