Tools Blog

HTTP Status Code Reference

Scan to open this page

Search every standard HTTP status code by number or name, with a plain-English summary first (not just raw RFC text), plus explicit "often confused with" notes for pairs like 401 vs 403 and 502 vs 503 vs 504.

How it works

  1. Type a code or keyword to search, or filter by 1xx–5xx category
  2. Each result shows a plain-English summary first, with the official RFC citation below
  3. Commonly confused codes (401/403, 301/302/307/308, 502/503/504) show an explicit comparison note

Frequently asked questions

What's the difference between 401 and 403?

401 Unauthorized means authentication failed or wasn't provided — "we don't know who you are." 403 Forbidden means the server knows who you are but won't authorize the request — "you can't do that."

What's the difference between 301, 302, 307, and 308?

301 and 308 are permanent redirects; 302 and 307 are temporary. 301/302 historically allow the method to change to GET on redirect (especially with older clients), while 307/308 explicitly preserve the original method and body.

What's the difference between 502, 503, and 504?

502 Bad Gateway means an upstream server returned an invalid response. 503 Service Unavailable means the server itself is temporarily overloaded or down for maintenance. 504 Gateway Timeout means an upstream server didn't respond in time.

Does this include nonstandard codes like 418?

Yes, marked explicitly — codes like 418 (I'm a teapot) and nginx's 444/499 aren't IETF standards but are widely implemented in the wild.

#HttpStatusCodesReference#HttpStatusCodeListSearchable#401Vs403WhichToUse#302Vs307Vs308RedirectDifference#HttpStatusCodeMeaningPlainEnglish

Related tools

URL Parser URL Parser MIME Type Lookup MIME Type Lookup

From the blog

httpstatuses.com — the site half the internet links to — now redirects to a marketing glossary
dev

httpstatuses.com — the site half the internet links to — now redirects to a marketing glossary

We visited the URL directly. It's not down, not parked — it redirects straight to an unrelated site's web development glossary page. Every old link to it is quietly broken.

2026-08-30

Update history

  • 2026-08-30 Added: a cover image (a row of numbered traffic-light-style badges for each status category, one showing a broken chain-link icon for dead reference links, another highlighted by a magnifying glass and double-arrow for code comparison) — used as the card thumbnail, social share image, and blog title image.
  • 2026-08-30 Launched: live HTTP status code reference (no button) — searchable/filterable list of all standard codes plus common nonstandard ones, plain-English summaries before RFC citations, and explicit "often confused with" notes for commonly mixed-up pairs. Entirely client-side.