Tuesday, August 12, 2008
We see two kinds of
404
("File not found") responses
on the web: "hard 404
error" and "soft 404
error." We discourage the use
of so-called soft 404
because they can be a confusing experience for users and search
engines. Instead of returning a 404
response code for a non-existent URL, websites
that serve soft 404
errors return a 200
response code. The
content of the 200
response is often the home page of the site, or an error page.
How does a soft 404
look to the user? Here's a mockup of a soft 404
:
This site returns a 200
response code and the site's home page for URLs that don't
exist.
![a user confused by a soft 404](https://developers-dot-devsite-v2-prod.appspot.com/static/search/blog/images/import/d7ee5595d67cc4369244bade38b53e40.png?authuser=2)
As exemplified above, soft 404
errors are confusing for users, and furthermore search
engines may spend much of their time crawling and indexing non-existent, often duplicative URLs
on your site. This can negatively impact your site's crawl coverage—because of the time Googlebot
spends on non-existent pages, your unique URLs may not be discovered as quickly or visited as
frequently.
What should you do instead of returning a soft 404
?
It's much better to return a 404
response code and clearly explain to users that
the file wasn't found. This makes search engines and many users happy.
![example of a 404 response header](https://developers-dot-devsite-v2-prod.appspot.com/static/search/blog/images/import/e2bc59570529ef251f4c327aae2a34bf.png?authuser=2)
![example error message returned to the user explaining that the content is not found](https://developers-dot-devsite-v2-prod.appspot.com/static/search/blog/images/import/7ffcd978d0497f3ee6021e60557a305d.png?authuser=2)
Can your webserver return 404
, but send a helpful "Not found" message to the user? Of
course! More info as
"404
week"
continues!