HTTP Status Codes.
Learn what HTTP Status Codes means in modern search and SEO.
Standardised three-digit numeric codes a web server returns to indicate the outcome of an HTTP request.
HTTP status codes are three-digit responses a web server sends when a browser or crawler makes a request. The first digit identifies the class: 1xx (informational), 2xx (success), 3xx (redirection), 4xx (client error), and 5xx (server error). Understanding status codes is fundamental to technical SEO, as they directly determine how Googlebot crawls, indexes, and passes link equity between pages.
Status Code Classes and SEO Impact
2xx codes (especially 200 OK) confirm a page is accessible and indexable. 3xx redirects transfer users and crawlers to a new URL—permanent 301s pass link equity; temporary 302s do not signal a permanent change. 4xx codes indicate client errors (404 Not Found, 410 Gone) that waste crawl budget. 5xx codes indicate server failures that prevent indexing entirely.
Monitoring Status Codes
Google Search Console's Coverage report groups URLs by status. Server log file analysis reveals the full distribution of status codes Googlebot encounters—including codes on URLs never linked internally. Screaming Frog and Sitebulb surface status codes during crawl audits, helping identify redirect chains, broken links, and soft 404s that inflate the 200-response count while delivering poor UX.
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