Your 404 Page: The Status Code It Must Send, and What to Put On It

What should a 404 page do?

Three terms, in the words of the people who define them:

• 404 Not Found: "the origin server did not find a current representation for the target resource or is not willing to disclose that one exists" (RFC 9110, section 15.5.5).
• 410 Gone: access "is no longer available at the origin server and that this condition is likely to be permanent" (RFC 9110, section 15.5.11).
• Soft 404: a page that "returns a user-friendly 'not found' message but not a 404 HTTP response code" (Google Search Console Help, Page indexing report).

What should a custom 404 page say?

WordPress puts the goal in one line: your 404 page should give "your visitors a way to arrive at the right place", and its own example adds "some text and a search form" (WordPress Theme Handbook, 404 pages). MDN allows some personality: "Feel free to make your 404 page humorous and human, but don't confuse your visitors as to why they are seeing something unexpected" (MDN, 404 Not Found). Here is the page we would build, part by part:

Which status code should a missing page send?

It depends on what happened to the page. Google's rule for the codes in the 400s is short: "All 4xx errors, except 429, are treated the same", and in Search "the indexing pipeline removes the URL from the index if it was previously indexed" (Google crawling docs, HTTP status codes).

Do 404 errors hurt SEO?

Not by themselves. Four beliefs we see often, each next to what Google says:

Should a removed page redirect, 404 or 410?

Answer two questions, in order, for every URL you take down:

How do I set up a 404 page that sends the right code?

Most setups send a real 404 by default. Each one below also has a setting that quietly turns it into a redirect or a 200: that is the line to check.

ErrorDocument 404 /errors/not-found.html

error_page 404 /404.html;

// app/not-found.tsx
export default function NotFound() {
  return <h1>We can't find that page</h1>
}

wp-content/themes/your-theme/404.php

# a file named 404.html at the site root
# _redirects, the single-page app rule:
/*  /index.html  200

# a file named 404.html at the top level
# of the build output folder

For a single-page app that cannot send a 404 from the server, Google names two fixes: "Use a JavaScript redirect to a URL for which the server responds with a 404 HTTP status code", or add a noindex robots meta tag to error pages with JavaScript (Google, JavaScript SEO basics).

How do I test my 404 page?

Make up a URL that cannot exist, such as /this-page-does-not-exist-2026, and score your site, one point per check:

1. The code is 404 (or 410). Run curl -s -o /dev/null -w '%{http_code}\n' https://example.com/this-page-does-not-exist-2026 with your domain. It sends a normal GET, like a browser or crawler, and must print 404 or 410. Single-page app that cannot send one? It also passes if the page carries noindex or redirects with JavaScript to a URL that returns 404; check the rendered HTML in Search Console's URL Inspection tool.
2. No redirect. The address bar still shows the made-up URL, unless you use that JavaScript redirect to a real 404 URL.
3. It looks like your site. Header, menu, fonts and footer load.
4. There is a way on. The search box returns results and every link opens a real page.
5. It works on a phone. Open it at phone width: no sideways scrolling, buttons easy to tap.
6. Search Console is quiet. In the Page indexing report, the "Soft 404" reason lists none of your real pages.

Questions site owners ask about 404 pages