Make a page-not-found experience that helps readers recover.

1. Distinguish a missing page from other failures

MDN defines a 404 response as the server being unable to find the requested resource. That code alone does not establish whether the absence is temporary or permanent. A login requirement, an outage, and a moved page are different situations and may need different handling.

Ask the builder to inspect the actual requested address and response. Do not turn every application failure into a cheerful “not found” screen. When content has a clear new home, use a deliberate page-move plan; when the address genuinely has no matching content, give the visitor a useful recovery experience.

Sources: [1]

2. Write a clear explanation

Use a direct heading such as “We couldn’t find that page,” followed by a brief next step. Keep the tone consistent with the site without blaming the visitor. An original ATN example is: “The address may have changed. Browse the guides or return to the homepage.”

Avoid claiming you know why the page is missing unless you have that information. A joke or illustration can support the design, but it should not obscure the message or become the only explanation. MDN’s guidance allows a human tone while emphasizing that visitors should understand why something unexpected appeared.

Sources: [1]

3. Offer a few working recovery routes

Google recommends keeping a custom 404 page consistent with the rest of the site and including useful destinations such as the homepage or relevant articles. Choose routes that help a person continue the task rather than presenting an overwhelming wall of unrelated links.

If you offer search, confirm that it works from the error page. If you invite broken-link reports, give people a functioning route and ask for only the information needed to investigate. Keep navigation understandable on mobile as well as desktop, including when the visitor landed directly from another website.

Sources: [2]

4. Verify the response as well as the design

Google describes a soft 404 as a missing or error page that returns a success response. A page can therefore look correct in a screenshot while sending a misleading status to clients. Ask the builder to test a deliberately nonexistent address and inspect the returned response.

Do not use the homepage as a catch-all destination for unrelated missing URLs. Record which paths are real moves and which are missing pages. This article is a design and verification guide; it does not change ATN’s routing or claim that any particular hosting setup already handles errors correctly.

Sources: [2]

5. Test the visitor’s next step

ATN suggests a small task-based review after implementation. Open a nonexistent URL directly, read the message, and follow the most useful recovery route.

Keep the tested address and result with the release notes. The error page helps visitors recover, but fixing a broken internal link still prevents the unnecessary detour in the first place.