HTTP Status Codes

HTTP Status Codes Reference - Complete List with Descriptions

Browse the complete list of HTTP status codes organized by category. Search by code number or description text.

Browse the complete catalog of HTTP status codes organized by category: 1xx (informational), 2xx (success), 3xx (redirection), 4xx (client errors), and 5xx (server errors). Click any category to filter the list or use the search box to find specific codes by number or description. Each code displays its standard name, a brief explanation of when it's used, and common scenarios. The reference covers all official IANA-registered codes plus common unofficial extensions. The lookup is instant and all data is stored locally.

Backend developers reference the tool when implementing API error handling to choose semantically correct status codes. Frontend engineers debug AJAX failures by looking up unfamiliar 4xx or 5xx codes returned by servers. Technical interviewers ask candidates about specific status codes; developers use this as a quick cheat sheet. DevOps teams investigating server logs look up rare codes like 418 (I'm a teapot) or 429 (Too Many Requests) to understand what triggered them.

Use 201 Created (not 200 OK) when POST requests successfully create new resources—clients may parse the Location header differently. The 204 No Content response should have an empty body; sending content violates the spec. 301 vs. 302 matters for SEO—301 permanent redirects transfer page rank, 302 temporary redirects don't. 401 Unauthorized actually means unauthenticated (no credentials), while 403 Forbidden means authenticated but not authorized. Use 422 Unprocessable Entity for validation errors, not 400 Bad Request.

All processing happens directly in your browser. Your files never leave your device — no server uploads, no cloud storage, no data retention. The tool works offline once loaded, requires no registration, and is completely free with no usage limits.