HTTP Status Codes Reference

By the FastFreeTools Editorial Team · Last reviewed: May 2026 · See our Editorial Policy for methodology, sourcing, and disclaimers.

Browse and search 25+ HTTP status codes organized by category with descriptions and use cases.

About this tool

HTTP status codes are three-digit numbers that web servers return to indicate the result of a client's request. Understanding these codes is fundamental to web development, API design, and debugging. Our interactive reference covers 25+ essential status codes organized by category: 1xx (informational), 2xx (success), 3xx (redirection), 4xx (client errors), and 5xx (server errors). Each code includes a clear description and common use case.

How to use HTTP Status Codes Reference

Browse status codes organized by category.
Search by code number, name, or description.
Read descriptions to understand each code.
Reference when building APIs or debugging.

Tips & best practices

2xx = success, 3xx = redirect, 4xx = client error, 5xx = server error.
401 = not authenticated; 403 = not authorized.
Use 301 for permanent redirects, 307 for temporary.
429 means rate limiting — slow down requests.

Common use cases

Designing RESTful API responses.
Debugging HTTP errors in dev tools.
Studying for web development interviews.
Configuring server error pages.

Privacy

This tool runs entirely in your browser. We do not upload, store, log, or process your input on any server. Open your browser's DevTools Network tab to verify — there is no outbound request with your data. See our Privacy Policy for details.

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