A 404 error (Not Found) is an HTTP status code returned when the server cannot locate the requested resource. The URL exists in the client's request but no matching content is found on the server.
Common Causes
- The page was deleted without setting up a redirect.
- A URL was changed and the old URL was not redirected.
- A typo in the URL.
- An external site links to a URL that no longer exists.
Soft 404 vs Hard 404
- Hard 404 — Server returns the 404 status code. Correct behaviour.
- Soft 404 — Server returns 200 OK but displays a "not found" message. Misleads search engines.
SEO and UX Best Practices
- Create a custom 404 page with navigation links and a search box.
- Set up 301 redirects for any deleted pages that had backlinks or traffic.
- Monitor Google Search Console for crawl errors.
- Fix or remove broken internal links pointing to 404 pages.