Definition
HTTP status codes are three-digit numbers a web server returns with every response to tell the client what happened with the request. They are grouped by first digit: 2xx means success (200 OK), 3xx means redirection (301 permanent, 302 temporary, 304 not modified), 4xx means a client error (404 not found, 403 forbidden, 410 gone, 429 too many requests), and 5xx means a server error (500 internal error, 503 service unavailable).
Search-engine crawlers use these codes to decide whether to index a URL, follow a redirect, drop a page, or slow down.
For SEO and site health, the codes a URL returns are as important as its content. A page that should exist but returns 404, a redirect that should be permanent but returns 302, a removed page that returns 200 with a "not found" message (a soft 404), or a server returning 5xx under crawl load all cause indexing and ranking problems that are invisible unless you check the actual response.
In context
On a large iGaming affiliate site, status-code hygiene is a recurring audit item. Common issues: reviews of closed operators returning 200 with an empty template (should be 301 to an alternative or 410 if genuinely gone), a migration that used 302 instead of 301 so ranking signal did not transfer, internal links pointing at URLs that now 404, and a fragile server returning 503 or 500 when the crawler requests many pages quickly, which reduces crawl rate.
The correct patterns: use 301 for any permanent URL change and update internal links to the new target rather than relying only on the redirect; use 410 for content deliberately and permanently removed so search engines drop it faster than a 404; return a proper 404 (not a 200) for URLs that never existed; keep 5xx rates near zero under normal crawl load; and after any redesign or migration, crawl the whole site and check that every URL returns the code it should. A monthly review of the search console's crawl-stats and page-indexing reports catches new status-code problems between full audits.
Worked example
An affiliate migrates to a new URL structure using 302 redirects because a developer used the framework default. Rankings drop over two weeks as signal fails to consolidate.
Switching the redirects to 301 and updating internal links restores rankings over the following month.
Related terms
Frequently asked questions
Browse the full iGaming & affiliate glossary — hundreds of EN/RU terms with examples.
← Back to glossary