HTTP status reference
Look up an HTTP status code, or list every code in the standard IANA registry range. Static table, runs on your device.
Runs on your device. The file is never uploaded.
HTTP status reference names a status code, so 404 comes back as the one line 404 Not Found. Typing all prints every entry the table holds, from 100 through 511, including 418 I'm a teapot. Nothing is fetched, and vendor codes such as nginx 499 and the Cloudflare 5xx set are missing.
Questions
What does it tell me about a code?
The official reason phrase, and only that. 404 comes back as "404 Not Found" and 429 as "429 Too Many Requests". There is no explanation, no advice on when to use it and no link, which makes it a fast lookup rather than a guide to designing an API.
How do I see every code it knows?
Type all in the code field. You get every entry in the table, one per line: the 1xx codes from 100 to 103, the 2xx family up to 226, the redirects, the full 4xx set and the 5xx set up to 511. The table is compiled into the page, so the list is identical on every run and works offline.
Why is my code not found?
Because it is not in the table. The message says the code is unknown and points you at typing all to see everything it knows. Codes that never made the standard registry are absent, and so are vendor extensions such as the Cloudflare 5xx codes and nginx 499. Only the standard set is listed.
Is 418 in there?
Yes, 418 I'm a teapot is in the table. It came from an April Fools RFC and was never a working HTTP status, but enough servers and test suites use it that leaving it out would surprise more people than including it. 306 is not in the table, since it was reserved and never assigned.
Does it check a live URL?
No. This is a reference table, not a request, so it never contacts a server and cannot tell you what status a given URL returns. Type the code you already saw in a log or in the network panel and it names it for you.