404 pages

A 404 error occurs when a page cannot be found on a web server.

Error pages

To help make our websites more user friendly, 404 pages should be designed to help the lost user. Try to direct your user to somewhere helpful, like home or search.

Use simple language and explain what happened but don’t accuse your user. Most people don’t actually know what a 404 page is, so explain how they got there.

Try not to use “404” as the primary message on the page, using it subtly is often better.

Customized and fun 404 pages are great to cheer up your users in a negative situation, but make sure they are still extremely helpful—helpfulness before fun.

Why would I see a 404 page?

The server will display a 404 error and page whenever a document cannot be found at the specific URL.

Here’s some examples of how that may happen:

  • A mis-typed URL, or an out-of-date bookmark
  • A search-engine link that’s out-of-date
  • An internal broken link that hasn’t been fixed

Other common error codes

  • 401 Unauthorized — the page can only be accessed by authorized users
  • 500 Internal Server Error — The server is having some issues

Setup

Each web server has a different way to set up 404 pages. The best way to start setting up your 404 page is to create a small HTML file named 404.html and style it. Afterwards you can set up your server to point to the document.

GitHub

If you’re hosting your website on GitHub, everything is already set up, you just need to make the file.

  1. Create an HTML file named 404.html
  2. Put it into your GitHub repo and commit and sync it

404 pages will only work on GitHub if you’re using a custom domain.

When using Jekyll

If you’re using Jekyll on your website and specifically using layouts and permalink: pretty, Jekyll will remove the extension from your file—but GitHub needs the file to be named “404.html”.

So, at the top of your 404 page, in the YAML data, add a permalink entry:

---
permalink: 404.html
---

Links

Apache web server

If you’re hosting your website on another host, many shared hosting environments use the Apache Web Server, so here’s some instructions for setting up the 404 page.

  1. Create an HTML file named 404.html
  2. Make a file named .htaccess and put it in the root of your website
  3. Put this in your .htaccess file:
ErrorDocument 404 /404.html
# You can specify pages for other error codes too
ErrorDocument 500 /500.html

This may not work on every web host, so check their documentation to see if they recommend another method.

Examples