HTTP 404 Not Found — What It Means and How to Fix It

HTTP 404 Not Found is a client-error status code meaning the server couldn't find any resource matching the requested URL. It doesn't necessarily mean the resource never existed — only that the server has no current mapping for that path.

Common causes

• The URL was typed incorrectly or a link points to a path that was moved, renamed, or removed
• A single-page application's client-side routes aren't configured on the server, so a direct visit or refresh to a deep link returns 404 instead of falling back to index.html
• A REST API endpoint path or an ID in the URL doesn't correspond to any existing record

How to fix it

• Double-check the requested URL for typos and confirm it matches the actual route/file structure on the server
• For single-page apps deployed as static files, configure the web server to rewrite unknown paths to index.html (a 'catch-all' fallback) so client-side routing can take over
• For APIs, return 404 deliberately when a resource genuinely doesn't exist (e.g. GET /users/999 for a non-existent user) rather than a generic error

Example

HTTP/1.1 404 Not Found
Content-Type: application/json

{"error": "User not found"}

FAQ

Is 404 the right code for 'the resource exists but you can't access it'?

No — that's 403 Forbidden. Some APIs deliberately return 404 instead of 403 for private resources to avoid revealing that the resource exists at all.