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DEVELOPER TOOL

HTTP Status Code Reference

Look up what any HTTP status code means.

About this tool

A quick-reference lookup for HTTP status codes — what each one means and when a server typically returns it. Search by the code number itself or a keyword like "redirect" or "unauthorized" to filter the list.

Frequently asked questions

What do the different hundred-ranges mean?
1xx are informational, 2xx mean success, 3xx are redirects, 4xx are client errors (the request was wrong), and 5xx are server errors (the server failed to fulfill a valid request).
What's the difference between 401 and 403?
401 Unauthorized means authentication is required or has failed. 403 Forbidden means the server understood who's asking but is refusing the request regardless of credentials.
Does this list every possible status code?
It covers the standard, commonly encountered codes. Some frameworks and APIs use additional non-standard codes for specific purposes not listed here.
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