Glossary · SEO

What is a 404 error?

Most 404s are harmless. The few that sit on pages with backlinks, traffic or internal links quietly drain rankings and send ready-to-buy visitors to a dead end.

The short answerA 404 error is the HTTP status code a server returns when it finds no page at the requested address. It usually appears after a page is deleted, moved without a redirect, or linked with a typo. 404s on unimportant URLs are normal; 404s on pages with links or traffic waste ranking value and lose visitors.

How a 404 error works

Every time a browser or crawler requests a URL, the server replies with a three-digit status code. 200 means the page loaded. 301 means it moved. 404 means the server found nothing at that address, so it shows an error page.

Common causes include a deleted product, a renamed page with no redirect, a typo in a link, or an old URL structure left behind after a redesign. Search engines that hit a 404 eventually drop that URL from the index. Visitors who hit one usually leave.

Say a distributor’s buyer clicks a link in a two-year-old trade article that points to your “industrial dust collectors” page. You renamed that page last spring. The buyer lands on a blank error screen, hits the back button, and calls the next supplier in the article. One missing redirect just cost you a qualified lead.

Know the variants

404, soft 404 and 410

Hard 404

The server returns status 404 and an error page. This is the correct, honest response for a URL with nothing behind it.

Soft 404

The page says “nothing here” or shows almost no content, yet the server returns 200 OK. Google flags these in Search Console because they waste crawling and confuse indexing. Redirecting retired pages to the homepage often creates them.

410 Gone

A stronger signal that the page was removed on purpose and will stay gone. Search engines may drop a 410 URL a little faster than a 404. Use it for content you deleted deliberately.

When 404s hurt, and when they are fine

Google has said for years that 404s on URLs that should be gone do no harm to the rest of your site. Every site collects them. The ones worth fixing fall into three groups:

  • Pages with backlinks. Links from other sites to a dead URL pass no value. A 301 to the closest live page recovers it.
  • Pages linked from your own site. Broken internal links waste crawl budget and strand visitors. Fix the link itself.
  • Pages that still get traffic. If people keep arriving at a dead URL from search, ads or email, they need somewhere useful to land.

404s also matter for AI search. AI crawlers fetch pages to answer questions, and a citation that points to a dead page sends the reader nowhere. Keeping your cited pages live and stable protects the visibility you earned. We explain the fetch-and-cite process in how AI search works, and our SEO services keep those pages healthy.

How to decide what to do with a 404

404 triage decision flow Start with a URL returning 404. If your own pages link to it, fix the link at the source. If it has backlinks or traffic, 301 it to the closest match. If it has neither, leave it as a 404, or return 410 if you removed it on purpose. URL returns 404 Linked fromyour own site? Fix link at source Backlinksor traffic? 301 to closest match Neither? Leave as 404, or 410 Then check your 404 page helps people
Fix your own links first, recover pages that still earn links or traffic, and let the rest stay gone.

How to find and fix 404s

  1. Open the Page indexing report in Google Search Console and review “Not found (404)” and “Soft 404.”
  2. Run a site crawler to list every internal link pointing at a 404.
  3. Check a backlink tool for dead URLs that still have links from other sites.
  4. Fix internal links at the source so they point at the live URL.
  5. Add a 301 for each valuable dead URL to its closest live match. See 301 redirect.
  6. Return a real 404 or 410 for everything else, and confirm soft 404s now send the right code.

What a helpful 404 page includes

A good 404 page keeps the visitor moving. Give it a plain message, a search box, links to your top service or product categories, and a clear way to contact sales. Make sure it still returns a 404 status code, so search engines read it correctly.

From our work

Some 404s are expected, and part of the job is knowing which ones to ignore. On alchemyleads.com, audit tools report 404s on Cloudflare’s /cdn-cgi/l/email-protection path. Those come from Cloudflare’s email address obfuscation, which hides our email addresses from spam bots. We keep that protection on and exclude the path from our audit counts, so the report shows only 404s that need action.

For client sites, we run the triage above on every technical SEO audit and after every redesign. When a fix involves a changed URL, we update the internal links at the source and keep the 301 as a fallback for outside links. On web design and development projects, we build the redirect map before a relaunch goes live, which keeps the 404 list short from the first day.

Related terms: redirect chain, crawlability, indexation, AI crawler, site migration.

Frequently asked questions

Do 404 errors hurt SEO?

404s on URLs that should be gone are normal and leave the rest of your site unaffected. They cost you when the dead URL has backlinks, internal links or steady traffic, because that value and those visitors are lost.

What is a soft 404?

A soft 404 is a page that looks empty or says the content is missing while the server reports 200 OK. Google treats it like a 404 and may drop it from the index. Fix it by returning a real 404 or 410, or by adding real content.

Should I redirect all 404s to the homepage?

No. Mass homepage redirects frustrate visitors and Google usually treats them as soft 404s. Redirect only to a closely matching page, and let the rest return 404.

What is the difference between a 404 and a 410?

Both say the page is unavailable. A 410 adds that it was removed on purpose and will stay gone, which can get it out of the index a little faster.

Revenue-first AI search

Turn dead ends into leads

We find the broken pages that cost you rankings and buyers, then fix them at the source so search and AI traffic keeps flowing.