404 page checker

Why a proper 404 matters

A 404 status code correctly signals that a requested page does not exist. Search engines rely on status codes to decide how to treat a URL. When a missing page returns a 200 status code instead, search engines may treat the error page as a real page, index it, and waste crawl budget. This can lead to duplicate or low-quality content appearing in search results and can confuse users who land on a page that looks like an error but claims success.

What this checker tests

The tool requests a generated URL that is unlikely to exist on the given website and records the HTTP status code returned. If the response code is 404, the server is correctly identifying missing content. If the response is 200 or another code, the site may be serving a soft 404, a generic page, or a redirect instead of a proper error response.

Soft 404s and why they matter

A soft 404 occurs when a missing page returns a success status code or redirects to an unrelated page. This behavior is problematic because search engines may index the error page, and users may be misled into thinking the content exists. Soft 404s are a common issue on sites with custom routing or single-page applications that always return a 200 response. Fixing them requires ensuring the server returns a 404 status for genuinely missing resources.

Limitations

This tool tests one generated URL against a single host. It does not crawl the site or verify that every missing page behaves correctly. Some sites intentionally redirect unknown URLs to the homepage or a search page, which may be a deliberate user experience choice but is not a true 404. The result reflects the status code observed at the time of the request; server configuration changes or caching can alter behavior. Use it as a quick check of error handling, not as a complete audit of all possible missing paths.