Why you need a custom error page

First, what is a 404 error page? Google provides a great definition:

A 404 page is what a user sees when they try to reach a non-existent page on your site (because they’ve clicked on a broken link, the page has been deleted, or they’ve mistyped a URL)

Having a custom error page helps your visitors. Broken links or typos happen, so at the very least try to point them in the right direction. The apple.com error page is a great example.

What prompted me to write about this is that the Yahoo! Store platform presents a special case because the default behavior is to send visitors to the homepage, so it’s a “soft” 404 error page. It’s described here along with simple instructions on how to set up a custom 404 page.

We checked several hundred Yahoo! Stores and found that only a third of them are using custom error pages.
Proportion of custom error pages
Here is why I think you should create a custom error page:

1) If a page is in fact no longer available it’s OK to let the visitor know that. Sending her to the homepage is not really what one would expect to happen.

2) As a site owner you don’t know that there is a broken link if you send visitors to the homepage. If you have a custom error page you can track it in web analytics. You can’t fix a problem if you don’t know about it.

3) Redirecting to the homepage could be seen as duplicate content and decreases the efficiency of spiders crawling your site. Returning anything but a 404 response for a non-existent page also means that you won’t be able to use the Crawl Errors report in Google Webmaster Tools – hat tip to Dave Burke for these points.

I know that to-do lists are getting longer and longer, but this is one thing you should do. So head on over here.