4XX Errors

4xx errors (also referred to as 400 errors) occur when a page that once existed on a website is no longer live and has not been redirected elsewhere. These HTTP 4xx status codes (such as a 404 error) can also impact SEO. There are a number of ways search engines view and deal with pages displaying 4xx error codes.
Learn how Google Search views 400 errors on your website (and how to solve 4xx issues for better organic search results) in this collection of ‘SEO Office Hours’ notes.
For more on 4xx errors, see our article on how to find 404 errors on your site.

Redirecting to 404 is OK

February 6, 2016 Source

A 302 redirect to a 404 page is OK

PageRank to 404 Pages is Lost

January 29, 2016 Source

If a site links to an external page which returns a 404, the PageRank will be lost.

404 Pages Crawled Less Than Noindex

October 27, 2015 Source

For expired/removed content, John says that Google prefer a 404 as it results in less crawling than a noindex.

Redirect Expired Pages to Alternatives or 404

October 16, 2015 Source

Out of stock/expired pages can be managed in a variety of ways. If there is a relevant alternative product, or a category page with good alternatives, a redirect is OK, otherwise a 410/404 is best.

301/404 Won’t Cause Ranking Problems

December 16, 2014 Source

Large numbers of 301 redirects and expired/low value URLs which 404 won’t directly cause any general ranking problems for the site (assuming you’re doing them properly and not losing important pages). But try to avoid chains of mutliple redirects.

Soft 404 Errors Can Identify Thin Pages

November 7, 2014 Source

The Soft 404 errors report in Webmaster Tools is a good way of identifying thin pages which Google don’t think have any original content.

Related Topics

5XX Errors Redirects