404 Error
A 404 error is an HTTP status code that tells the client the server could not find the requested page or resource. It does not distinguish between a resource that is temporarily missing and one that has been permanently removed.
- A 404 error is a 4xx-class HTTP status code signaling that the server could not find the resource at the URL the client requested.
- A 404 is a normal part of the web and does not hurt the search rankings of other, working pages on the site.
- A soft 404, which disguises a missing page behind a success (2xx) response, is worse because it confuses indexing; returning a real 404 or 410 is preferable.
- Use a 404 for pages that might come back, a 410 for pages that are permanently gone, and a 301 redirect when content has simply moved to a new location.
Overview
A 404 error is the HTTP status code a server returns when it cannot find the page or resource a browser or client requested. Its formal name is "404 Not Found," and it belongs to the 4xx class of client errors. In a browser it means the entered URL was not recognized; in an API it means the endpoint is valid but the specific resource does not exist.
Crucially, a 404 says nothing about whether the resource is temporarily unavailable or permanently gone. When a resource has been removed for good, the server is encouraged to use the 410 Gone status code instead. Links that lead to a 404 are commonly called "broken" or "dead" links.
Common causes of a 404 include mistyped URLs, pages that were moved or deleted without a redirect, and internal or external links that point to the wrong address.
SEO Perspective
A 404 error is a perfectly normal occurrence on the web. Google states plainly that having 404s on a site does not affect the search rankings of other URLs that return a 200 success code. Search engines have 404s on their own sites too, and they treat them as a routine condition.
That said, an excessive number of 404s creates two problems. First, visitors who click a broken link hit a dead end, degrading the user experience (UX). Second, when crawlers repeatedly request URLs that do not exist, crawl budget can be wasted. For these reasons it is best to keep the number of broken internal and external links to a minimum.
404 vs. Soft 404 vs. 410
The three differ in meaning and in how they should be handled.
- 404 (Not Found) — The resource could not be found. It does not state whether the absence is temporary or permanent, making it appropriate when a page may come back.
- Soft 404 — A page that does not actually exist, yet the server returns a 2xx success code for it. When an empty page or an error message such as "page not found" is served alongside a 200 code, Google classifies it as a soft 404. Because it masquerades as success, it interferes with how search engines understand indexing and is treated as a worse signal than a proper 404 or 410.
- 410 (Gone) — Explicitly signals that the resource has been permanently removed and will not return. Google treats 404 and 410 essentially the same during indexing (all 4xx errors except 429 are handled alike), removing the URL from the index in both cases and gradually reducing how often it is crawled.
Correct Handling
The key when deleting a page is to return a proper 404 or 410 response code rather than creating a soft 404. Use a 404 if the page might come back, and a 410 if you are confident it is gone for good. If the content has moved elsewhere, connecting users to the new address with a 301 permanent redirect, instead of a 404, serves both visitors and search engines better.
It is also good practice to provide a custom 404 page that helps users escape the dead end. A custom 404 page can include a site search box, links to popular content, and a path back to the home page. Note, however, that a custom 404 page must still return a 404 status code rather than HTTP 200; otherwise it becomes a soft 404 itself.
Basis
The points above draw on MDN's 404 Not Found documentation (a 404 does not distinguish temporary from permanent, and 410 is recommended for permanent removal), the Google Search Central blog (404s do not affect the rankings of other pages, and soft 404s should be avoided), and Google's HTTP status code documentation (404 and 410 are handled identically, with a definition of soft 404).
Action Checklist
- Audit broken internal and external links, then fix or remove them.
- Confirm that deleted pages return an appropriate 404 or 410 status code.
- Check that no non-existent pages return a 200 code, creating a soft 404 situation.
- Distinguish handling by intent: 410 for permanently deleted pages, 404 for pages that can be restored.
- When content has moved, connect the new URL with a 301 permanent redirect instead of a 404.
- Offer a custom 404 page with a search box, key links, and a path home, while keeping the status code as 404.
- Periodically monitor 404 and soft 404 trends in Search Console's indexing report.