HTTP Status Codes Explained: 1xx, 2xx, 3xx, 4xx and 5xx

About these videos

Every time a browser asks a server for a page, the server answers with a three-digit HTTP status code. The first digit tells you the class: 1xx informational, 2xx success, 3xx redirect, 4xx a problem with the request and 5xx a problem on the server.

These two short videos explain what status codes are and the 1xx informational codes. Below is a quick guide to the codes you will meet most often when managing a website.

What you will learn

• 200 OK: the page loaded normally
• 301 Moved Permanently: a permanent redirect that passes SEO value
• 302 Found: a temporary redirect
• 404 Not Found: the page does not exist; fix or redirect important ones
• 500 Internal Server Error and 503 Service Unavailable: problems on the server

Quick answers

Which status codes matter for SEO?

Mostly 200, 301, 404 and 5xx. Google Search Console reports pages with these problems.

How do I check a page’s status code?

Open the browser’s DevTools Network tab and reload the page, or use an online HTTP status checker.

Try it yourself: Open the Pages report in Google Search Console and look for any “Not found (404)” URLs.

Watch next

HTTP status codes part 2: 1xx informational