HTTP Status Code Reference

Look Up Any Status Code — Instantly, With Real Usage Guidance

Search or filter all standard HTTP status codes from 1xx through 5xx, plus common unofficial codes like Cloudflare's 520s and nginx's 444. Every code includes a plain-English meaning, practical usage guidance, and the easily-confused codes nearby — not just a dictionary definition.

🔒 Runs entirely in your browser — nothing you type is ever transmitted to any server

Need to check what code a real URL returns right now? This page explains what each code means. To inspect the live status code and headers for an actual URL, use the HTTP Header Checker.

Open HTTP Header Checker →

No status codes match your search. Try a different code number or keyword.

All lookups run locally in your browser. No search terms or status codes you view are ever transmitted to a server.

How to Use the HTTP Status Code Reference

Search or Filter

Type a status code number or keyword into the search box, or click a class filter pill (1xx, 2xx, 3xx, 4xx, 5xx, or Unofficial) to narrow the list instantly. Results update as you type — there's no separate search button to click.

Click a Code to Expand It

Click any status code card to expand it and reveal the full plain-English explanation, practical usage guidance, and an RFC reference where one exists. Click again to collapse it.

Copy the Code and Name

Click the copy icon on any code's header to instantly copy the code number and name (e.g. 404 Not Found) to your clipboard — handy for documentation, support tickets, or commit messages.

Check a Live URL

This page explains what codes mean — it doesn't make live requests. To see what status code a real URL is actually returning right now, use the HTTP Header Checker, linked above the lookup tool.

Frequently Asked Questions

What is an HTTP status code?

What is the difference between 401 and 403?

What is the difference between 409 and 422?

Is 418 I'm a Teapot a real status code?

Why do I see status codes like 520 or 521 that aren't in any official list?

Where can I check what status code a live URL is actually returning?

HTTP Status Code Reference

How to Use the HTTP Status Code Reference

Frequently Asked Questions

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