How do I make a good custom 404 page?

Create a page that says plainly the address was not found, keeps your normal header and navigation, offers a search box and links to your main sections, and returns a real 404 status code. The status code matters as much as the design, because a friendly error page that answers 200 is treated as a soft 404.

Why it matters

Everyone mistypes addresses and old links break. A helpful error page keeps those visitors on your site instead of sending them back to the search results. A page that returns the correct 404 status also tells search engines the URL does not exist, so it is not indexed.

How to do it

Write a clear headline such as "We could not find that page" and one short sentence explaining that the link may be old or mistyped.
Keep your normal site layout: logo, navigation and footer, so the visitor can carry on.
Add useful routes out: a search box, a link to the home page and links to your most visited sections or products.
Keep the tone friendly and short. Avoid jokes that hide the message, and avoid automatic redirects to the home page.
Do not index it. The page should return a 404 status, which is enough on its own for search engines.
Configure the server so the custom page is shown for missing URLs while the status stays 404. In nginx:

error_page 404 /404.html;

In Apache:

ErrorDocument 404 /404.html

In ASP.NET Core, a status-code pages handler that re-executes a path preserves the 404 status; avoid redirect-based options, which end in a 200. 7. Test with a made-up address:

curl -sI https://example.com/this-page-does-not-exist

The first line must show 404. Also open the address in a browser to check the layout. 8. Make the page work on a phone, with no horizontal scrolling. 9. Check Google Search Console later for "Soft 404" entries, which would show the status is wrong somewhere.

Common mistakes

Returning 200 for the error page.
Redirecting every missing URL to the home page.
Using the error page as a dead end with no links.
Loading heavy scripts or large images on the error page.
Letting the error page differ from the rest of the site, which makes it look broken.

Frequently asked questions

Should the 404 page have a noindex tag?

It is not needed when the page returns a 404 status, because search engines already treat the address as missing.

Should I log 404 errors?

Yes. Your server logs and Search Console show which broken addresses people reach. Fix frequent ones with a 301 redirect to the right page.

Yes, a search box is one of the most helpful things on an error page.

To test your own error page, Try the free website sample.