Learning Hub — Beginner's Guide
⭐ Beginner — No coding experience needed

What you will learn in this guide

1 What are HTTP errors?

When a browser or Google visits a page on your site, your server sends back a three-digit response code. A 200 means everything is fine. A 404 means the page does not exist. A 500 means something broke on your server.

CodeMeaningSEO impact
404 Not FoundPage does not existWastes crawl budget, may deindex page
410 GonePage permanently deletedGoogle removes it faster than 404
403 ForbiddenAccess deniedPage cannot be indexed
500 Server ErrorSomething crashed on your serverPage may be deindexed if persistent
503 UnavailableServer overloadedGoogle retries — persistent = deindex risk

2 How to find all errors on your site

  1. 1 Open the HTTP Error Audit Go to performance-tools.html#http-error-audit. Choose your scan size — 10 pages is enough for a small site, 50 pages for most business sites.
  2. 2 Enter your homepage URL and run the scan The crawler starts at your homepage, follows every internal link, and records the HTTP status of each page it visits. Results appear as the crawl progresses.
  3. 3 Filter by 4xx errors first Click the "4xx Errors" filter to see only broken pages. The "Found on" column shows which page linked to the broken URL — so you know exactly where to remove or update the link.
  4. 4 Then check 5xx errors 5xx errors are server-side problems. If you see these, check your server error logs immediately — they indicate something is broken on your hosting or application.

3 How to fix a 404 error

For each 404 you find, you have three options:

  1. 1 Set up a 301 redirect If the page has moved or been replaced, redirect the old URL to the new one permanently. A 301 redirect passes the old page's authority to the new destination. In WordPress, use the Redirection plugin. In other systems, add the redirect to your .htaccess file or NGINX config.
  2. 2 Return a 410 Gone If the page is permanently deleted and has no replacement, return a 410 status code. This tells Google to remove the URL from its index immediately — faster than a 404.
  3. 3 Update or remove the linking page The "Found on" column in the audit shows which page linked to the broken URL. Go to that page and either update the link to the correct URL or remove it entirely.
After fixing: Run the HTTP Error Audit again to confirm the errors are resolved. Check the Redirects filter to make sure your 301 redirects are working and returning 200 at the destination.
Written by
John
Founder, AIWebPageSEO

404 errors are one of the most common SEO problems I see on client sites — and one of the easiest to fix once you know where they are. The problem is most site owners have no idea how many broken pages they have until they run an audit. This guide walks through the whole process.