Webmasters Stack Exchange is a question and answer site for pro webmasters. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Do the search engines take the number of 404 errors returned by a site into account when calculating the site rank? For example I have 8,000 404 errors and I am thinking that that's affecting my SEO in a negative way.

However, I read this Google Webmaster Central article about 404 errors which suggests that they are not always a negative quality indicator.

So I am confused...are high numbers of 404 errors harmful to a site or not?

share|improve this question
up vote 4 down vote accepted

It depends on why the 404 errors are coming up but in general terms, yes, high numbers of 404 errors can count against the quality metrics of your site and hurt your rankings.

Whenever Google spiders the web, they are following links from external sites to yours, your own internal structure, and your past indexed pages. While 404s themselves are not a negative indicator according to the linked article above, 404s of expected content due to errors in your internal linking or server configuration (i.e., a bad redirect rule) will lower the number of documents you have indexed and that is the "penalty" applied.

There are several things you can do to mitigate the effect of 404 errors:

  1. Use a custom 404 error page to suggest alternative navigation. The inbound user or robot should be presented links and a menu to assist them in finding other content on your site. Never leave a default 404 server-generated error page in place
  2. If the 404s are caused from external links, use 301 redirects to get the inbounds to the desired location
  3. Use an XML sitemap to tell search engines what exists. This helps to drop dead pages out of their indexes

Follow those simple steps and any penalty caused by excessive 404 errors should fall away over time.

share|improve this answer
Thank you man, that's a nice answer – Johan Aug 7 '13 at 22:52
You're welcome. – JCL1178 Aug 7 '13 at 22:52

Google's John Mueller says:

404 errors on invalid URLs do not harm your site’s indexing or ranking in any way. It doesn’t matter if there are 100 or 10 million, they won’t harm your site’s ranking.

(as long as the 404 isn't coming from pages you want to see ranking)

share|improve this answer
They are not pages, they are non-existing posts. Thanks Stephen! Nice! – Johan Aug 8 '13 at 5:54
If someone is linking to your site say CarA.html but they are linking using carA.html then you won't be getting the juice from their link so you could as a audience stand point and SEO be beneficial to 301 redirect to the right page. Otherwise if they are linking to pages about Cakes, but your site is about Cars then you should simply ignore it and leave it as 404 as this would not benefit you or your audience. Be sure to check out the page that says LINKED FROM to see if you have an internal link or external link doing it. – Simon Hayter Aug 8 '13 at 7:38
John also said recently if they see a lot of errors they slow down crawling – Pepone Jan 9 at 0:15

In Google Webmaster Tools it says 'they generally don't hurt your ranking.'

However, they are bad for user experience and search engines don't buy things.

To quote the Google Intro to SEO .pdf:

Blockquote ...you should base your optimization decisions first and foremost on what's best for the visitors of your site. They're the main consumers of your content and are using search engines to find your work.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.