Not Found
4xx Client Error
Last updated:
The server has not found anything matching the requested URL.
Description
The most famous HTTP error. Signals that the resource doesn't exist, but says nothing about whether it ever existed or will exist again. Search engines treat 404 as a signal to eventually drop the URL from the index.
When to use
Return 404 for missing resources. Also acceptable to hide protected resources you don't want to acknowledge.
Common pitfalls
A 404 must return an actual 404 status. Serving a friendly 'not found' HTML page with a 200 status is called a 'soft 404' and confuses search engines.
Also searched as
Developers commonly search for 404 using phrases like 404 not found · 404 error · http 404 · 404 not found meaning · page not found · 404 status code · soft 404. All refer to the same HTTP 404 Not Found response.
Specification
RFC 9110 §15.5.5
Examples
HTTP/1.1 404 Not Found
Content-Type: application/json
{"error":"Not Found"}res.status(404).json({ error: "Not Found" });w.WriteHeader(http.StatusNotFound)
return jsonify({"error": "Not Found"}), 404