SEOTechnical SEOUpdated 2026.04.28

404 Error

Also known asNot Found페이지 없음

In one line

A 404 error is the HTTP response signalling that the requested URL does not exist — affecting both user experience and crawl efficiency.

Going deeper

A 404 means 'this URL does not exist'. Some level of 404s is normal, but if a key category page or popular article is 404ing, you are losing traffic immediately.

Two practical levers: first, 301-redirect broken URLs that earned external links to a relevant live page so the equity is recovered. Second, ship a helpful 404 page with search and popular content links to keep users on the site.

Make a habit of reviewing the 'Page indexing' report in Google Search Console. A botched URL-structure change usually shows up here first.

Related terms

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