HTTP Status Codes
Look up any HTTP status code with its meaning, description, and use cases.
How to Use
- Type a code number (e.g. 404) or keyword (e.g. "not found") in the search box.
- Results filter instantly as you type.
- Click any code card to expand the full description and use cases.
- Use the category tabs to browse all 1xx, 2xx, 3xx, 4xx, or 5xx codes.
When to Use This
- Deciding which code an endpoint should return for a validation failure, where 400 and 422 both look defensible at first glance.
- Explaining to a stakeholder why a 410 on a removed page tells search engines something that a plain 404 does not.
- Looking up an unfamiliar code from a server log, such as 421 or 451, without leaving the tab you were debugging in.
- Settling which redirect to use for a domain move, by comparing what 301, 307 and 308 each promise about the method.
Frequently Asked Questions
About This Tool
An HTTP status code is the first thing a client learns about a response, and its class tells the client what to do before it reads a byte of the body. The distinctions that matter in practice sit inside a class. 401 means the request carried no valid credentials while 403 means credentials will not help. 302 historically allowed clients to rewrite a POST into a GET, which is exactly why 307 and 308 exist: they promise the method and body survive the redirect.
This page carries sixty-one codes inside the script itself, so no lookup request is made and filtering happens as you type. The tabs narrow the list to a single class, and the search box matches the number, the name and the description text, so a search for rate limit finds 429 even though those words are not in its name. Clicking a row expands its description.
Notes & Limits
- Sixty-one codes are listed. Vendor extensions such as Cloudflare's 520 to 526 or nginx's 499 are not among them and will not be found.
- This is a reference, not a diagnosis. It can say what a 502 is defined to mean but not why your particular gateway returned one.
- Each entry gives a definition and typical usage only; it does not state which codes are cacheable by default or which methods they apply to.
- Descriptions are summaries rather than specification text, so check the current RFC when the exact required response headers matter.