What it means
The server cannot find anything at the requested URL. It says nothing about whether the resource ever existed or might return.
Common causes
- Typo or outdated link
- The page was moved or deleted without a redirect
- Wrong route, base path or case-sensitive file name
How to fix it
As a client or visitor
Check the URL spelling and case, remove trailing characters, and look for the content through the site's search or home page.
As the site or API owner
Add 301 redirects for moved content, fix broken internal links, and serve a helpful 404 page that still returns status 404. Use 410 for content removed on purpose.
Example response
HTTP/1.1
HTTP/1.1 404 Not Found
Date: Tue, 07 Oct 2025 09:30:00 GMT
Server: nginx
Content-Type: application/problem+json
{
"type": "about:blank",
"title": "Not Found",
"status": 404,
"detail": "No user with id 42."
}Specification
FAQ
› Do 404 errors hurt SEO?
404s for pages that never existed are normal. Fix broken internal links and redirect valuable moved pages so their signals are not lost.
› Why does my single-page app return 404 on refresh?
The server looks for a file at that path. Configure it to serve index.html for unknown routes, or prerender the routes.