404 SEO

A 404 is an HTTP status code indicating the server could not find the requested URL. For SEO, most 404s are harmless, but important ones need attention.

Also called: Not Found error
Applies to: Web pages, images, videos, any URL
Commonly confused with: 410 Gone, 301 redirect

Key points

Most 404 errors do not harm indexing or ranking by themselves.
Redirect important 404s to the most relevant replacement URL using a 301.
Do not redirect all 404s to the homepage or block them with robots.txt.
A custom 404 page can improve user experience by helping visitors find alternatives.
Audit broken internal links, outdated sitemaps, and deleted pages with backlinks.

Why it matters

A 404 tells browsers and search engines that a requested URL does not exist. For SEO, 404s matter mainly when they affect important URLs, internal links, sitemaps, or pages with backlinks. Google states that most 404 errors do not hurt indexing or ranking by themselves, so the question 'do 404 errors hurt seo' is often answered with 'it depends'. However, submitted or strategically important URLs should be fixed, redirected, or intentionally left as 404 or 410 depending on the case. 404s can also apply to missing files such as images or videos, and in the context of ajax seo, a missing AJAX endpoint returning 404 can break dynamic content.

Google's guidance can evolve, but the core rule remains that most 404s are normal and only important ones need action.

Where it changes your decision

When a page with backlinks returns 404: decide whether to redirect to a relevant replacement or leave it as 404/410 if the content is permanently gone.
When internal links point to 404s: fix or redirect them to avoid wasting crawl budget and confusing users.
When a sitemap contains 404 URLs: update or remove them to prevent search engines from wasting resources on dead pages.

For a detailed guide on handling 404s, see our article on seo 404 page best practices.

Questions people ask

Are 404 errors bad for SEO?

Most 404 errors are not bad for SEO by themselves. Google says they do not harm indexing or ranking unless they affect important URLs such as those with backlinks, internal links, or those submitted in sitemaps. The key is to assess each 404's context and act only when necessary.

SEO 404 page best practices?

Best practices include: using a 301 redirect if the content has moved to a relevant replacement; returning 404 or 410 if the content is permanently removed and no close replacement exists; creating a custom 404 page that helps users find alternatives; and avoiding redirecting all 404s to the homepage or blocking them with robots.txt.

What to do with 404 pages?

If the content has moved, set up a 301 redirect to the most relevant replacement URL. If the content is permanently removed and has no close replacement, leave it as 404 or use a 410 status. For pages with no value, do nothing. Always fix broken internal links and update sitemaps to remove dead URLs.

Sources

Google Search Console Help: 404 (Page Not Found) errors Best source for Google’s guidance on when to fix, redirect, or leave 404s.
Google Search Central Official documentation on HTTP fetching and how Google handles crawl errors and status codes.
RFC 9110 Defines the HTTP 404 status code at the protocol level.
Google Search Central: Site move with URL changes Useful for canonical redirect practice when URLs change.

Written and maintained by Nora Lindholm. Last updated 27 July 2026.

Spotted an error? Email me — corrections are logged and credited on the entry. Outbound links are unpaid; most are nofollow.