HTTP Status Codes Reference

Developer References100% Client-Side

Comprehensive, searchable cheat sheet of all standard HTTP response status codes with detailed explanations.

100Continue

Client should continue with its request.

101Switching Protocols

Server is switching protocols (e.g. WebSocket handshake).

200OK

The request has succeeded.

201Created

Resource has been successfully created.

202Accepted

Request accepted for background processing.

204No Content

Request succeeded, but no content in response body.

301Moved Permanently

Resource permanently moved to a new URL.

302Found (Temporary Redirect)

Resource temporarily moved to a new URL.

304Not Modified

Cached version is up to date (conditional GET).

307Temporary Redirect

Redirect maintaining same HTTP method.

308Permanent Redirect

Permanent redirect maintaining same HTTP method.

400Bad Request

Malformed request syntax or validation error.

401Unauthorized

Authentication is required or invalid.

403Forbidden

Authenticated, but access is not allowed.

404Not Found

Resource could not be found.

405Method Not Allowed

HTTP method not supported for resource.

409Conflict

Request conflicts with current state of resource.

422Unprocessable Entity

Semantic errors in request body.

429Too Many Requests

Rate limit exceeded.

500Internal Server Error

Unexpected server error.

502Bad Gateway

Invalid response from upstream backend server.

503Service Unavailable

Server is overloaded or down for maintenance.

504Gateway Timeout

Upstream server failed to respond in time.

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What is HTTP Status Codes Reference?

Complete reference guide of all standard IANA HTTP status codes categorized into 1xx (Informational), 2xx (Success), 3xx (Redirection), 4xx (Client Errors), and 5xx (Server Errors).

Key Features

Instant search filter by code number or description keyword
Categorized by status class with color-coded visual badges
Includes practical troubleshooting tips for each error code
Quick copy code and title

Common Use Cases

  • Choosing appropriate HTTP status codes when designing RESTful APIs
  • Diagnosing web server errors (e.g. 502 Bad Gateway, 504 Gateway Timeout)
  • Understanding client authentication errors (401 Unauthorized vs 403 Forbidden)

Frequently Asked Questions

401 Unauthorized means authentication is missing or invalid (you are not logged in). 403 Forbidden means authentication is recognized, but you lack permission to access the resource.