HTTP Status Codes

A free online reference that lists every HTTP status code defined by IANA — from the familiar 200 OK and 404 Not Found to the nuanced 418 I'm a Teapot and the HTTP/2-specific 425 Too Early. Search by number or keyword and immediately see the category, official description, and typical use scenario. HTTP status codes are grouped into five families. 1xx codes carry provisional information, 2xx signals success, 3xx handles redirects and caching, 4xx flags client errors (bad requests, missing auth, rate limits), and 5xx indicates the server ran into trouble. Knowing these families lets you triage problems fast — a 502 Bad Gateway points upstream, while a 401 Unauthorized points at your credentials. Developers reach for this reference daily: choosing the right code when designing a REST API (should a soft delete return 200 or 204?), diagnosing why a fetch call failed (is it CORS, a bad token, or a server crash?), or writing middleware that maps errors to appropriate responses. Each entry explains whether the code is standardized, which browsers and frameworks support it, and how it differs from similar codes — for instance, 403 Forbidden versus 401 Unauthorized, or 301 versus 302 redirects. The entire lookup runs in your browser with an offline-capable database, so it's handy even on flaky connections.