HTTP Status Codes
Search, copy, and link straight to any row.
HTTP status codes are the three-digit numbers a server returns to tell a browser or API client what happened with a request. They fall into five families: 1xx informational, 2xx success, 3xx redirects, 4xx client errors, and 5xx server errors. This table lists the codes you'll actually meet, with plain-language meanings. Search it, copy any row, or link straight to a specific code.
How to use it
- Type in the search box to filter by code, name, meaning, or class.
- Use the copy button on any row to grab it for documentation or a ticket.
- Link directly to a code by adding it to the address, for example #row-404.
Examples
- 404 Not Found — the resource does not exist at this URL.
- 429 Too Many Requests — you are rate limited; check the Retry-After header.
Frequently asked questions
- What is the difference between 301 and 302?
- A 301 says the resource has moved permanently, so clients update their links and search engines transfer ranking signals to the new URL. A 302 says the move is temporary, so the original URL keeps its standing. Using 302 for a permanent move is a common and costly SEO mistake.
- Why am I seeing a 502 Bad Gateway?
- A 502 means a server acting as a proxy or gateway received an invalid response from the server behind it. Usually the upstream application has crashed, is still starting, or is overloaded — check the application logs rather than the proxy itself.
- When should an API return 422 vs 400?
- Return 400 when the request itself is malformed — broken JSON, missing required structure. Return 422 when the syntax is fine but the content fails validation, such as an email field containing something that is not an email. The distinction helps clients know whether to fix the format or the values.
- Is 418 a real status code?
- It is real in the sense that it is defined — in RFC 2324, an April Fools' joke specification for a coffee-pot protocol, where 418 means the server is a teapot. It is not part of standard HTTP, but it is widely implemented as an Easter egg and attempts to remove it have been resisted.