Look up an API error
Search 429, 502, or timeout to understand what a response code usually means.
HTTP Status Lookup
Search common HTTP status codes by number, category, or meaning.
404 Not Found
Client error
The requested resource was not found.
Matching status codes
About HTTP status codes
HTTP status codes describe the result of a request. They help clients, APIs, proxies, and browsers understand whether a request succeeded, redirected, failed on the client, or failed on the server.
Common uses
- Look up an API response code
- Check redirect behavior
- Explain client and server errors
- Debug crawler or uptime reports
Examples
Check redirect codes
Compare 301, 302, and 304 when debugging browser, crawler, or CDN behavior.
FAQ
What do 4xx HTTP status codes mean?ShowHide
4xx codes usually indicate a client-side problem, such as a missing resource, failed authentication, or invalid request.
What do 5xx HTTP status codes mean?ShowHide
5xx codes usually indicate a server or upstream problem, such as an internal error, bad gateway, or gateway timeout.
Does this tool make a request to my URL?ShowHide
No. It is a lookup table for common status codes and meanings.