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What Is 404 Error?

Updated 18 September 2026

Quick Answer

A 404 error is the message a browser shows when a requested webpage can't be found — usually because the page was deleted, moved, or the URL was typed or linked incorrectly.

404 Error vs. 301 Redirect — What's the Difference?

404 Error301 Redirect
What happensThe page is genuinely gone, visitor hits a dead endThe page has moved, and the visitor is automatically sent to the new location

Why It Matters

  • A visitor hitting a 404 error usually leaves immediately, especially if it happens on a link they trusted (like from an ad or another site).
  • Search engines that repeatedly encounter 404s on previously working pages can lower trust in a site's overall health.

How It Works

  1. A browser or search engine requests a specific URL.
  2. The server can't find any content at that address.
  3. It returns a 404 status code, and the browser displays an error message to the visitor.

Key Takeaways

  • A 404 error means a requested page can't be found.
  • It usually causes an immediate visitor exit, especially from a trusted link.
  • A 301 redirect fixes it when the content has simply moved.

Frequently Asked Questions

How do I find 404 errors on my site?

Google Search Console reports crawl errors, including 404s, directly.

How do I fix a 404 error?

If the content still exists at a new location, add a 301 redirect; if it's genuinely gone, consider redirecting to a relevant related page instead of leaving a dead end.

Should I customize my 404 page?

Yes — a helpful custom 404 page (with a search bar or links to popular pages) can recover a visitor who might otherwise leave immediately.