Complete reference for all HTTP status codes with search and filtering
Quick Reference
What are HTTP Status Codes?
HTTP status codes are three-digit numbers returned by a server in response to a client request. They are grouped into five categories — informational (1xx), success (2xx), redirection (3xx), client errors (4xx), and server errors (5xx) — and are essential for debugging APIs, web applications, and infrastructure issues.
How to Use This HTTP Status Codes Reference
Use the quick reference buttons to look up common status codes instantly
Search by code number, name, or description using the search bar
Filter by category (1xx–5xx) to narrow down results
Click any status code card to expand its full description and common use case
Common Use Cases
Debugging API responses and understanding why a request failed
Implementing correct HTTP error handling in web applications
Configuring server redirects and understanding cache behavior
Learning which status codes to return from REST API endpoints
Frequently Asked Questions
What is the difference between 301 and 302 redirects?
A 301 Moved Permanently tells browsers and search engines the resource has permanently moved, and they should update their bookmarks and indexes. A 302 Found indicates a temporary redirect — the original URL should still be used in the future.
When should I use 422 vs 400?
Use 400 Bad Request when the request itself is malformed (invalid JSON, wrong syntax). Use 422 Unprocessable Entity when the request is well-formed but contains semantically invalid data (e.g. a negative age or an email without an @ sign).
What is a 429 status code and how should I handle it?
429 Too Many Requests means you are being rate-limited. The response often includes a Retry-After header telling you how long to wait before trying again. Implement exponential backoff in your client to handle this gracefully.