What Is HTTP Status Code (200, 404, 500 Explained)
HTTP status codes tell you what happened with a web request. Learn what 200, 301, 404, 500 and other codes mean — in plain English.
Every time your browser asks a server for something, the server responds with a 3-digit HTTP status code. They're grouped into five families.
The 5 Families
- 1xx — informational (rarely seen)
- 2xx — success
- 3xx — redirect
- 4xx — client error (your fault)
- 5xx — server error (their fault)
Check the status code of any URL with our HTTP Header tool.
Open Header CheckerCodes You'll Actually See
200 OK
Everything worked. The page loaded successfully.
301 Moved Permanently
The URL has permanently moved. Search engines pass nearly all SEO value to the new URL.
302 Found
Temporary redirect. SEO value is split.
404 Not Found
The page doesn't exist on the server. Common when you mistype a URL or follow a broken link.
500 Internal Server Error
Something broke on the server. Not your fault — try again later or contact the site owner.
503 Service Unavailable
Server is overloaded or down for maintenance.
Why Status Codes Matter for SEO
Search engines use them to decide whether to index, follow or drop URLs. Too many 404s or 500s can hurt your rankings.
Audit any page's response headers in seconds.
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