What is an HTTP status code?

An HTTP status code is a three-digit number in every server response that tells the client what happened with the request. The first digit indicates the category: 1xx (informational), 2xx (success), 3xx (redirection), 4xx (client error), 5xx (server error).

What is the difference between 401 and 403?

401 Unauthorized means the request lacks valid authentication credentials — the server doesn't know who you are. 403 Forbidden means you're authenticated but don't have permission to access the resource — the server knows who you are but won't let you in.

What is the difference between 301 and 302?

301 is a permanent redirect — browsers and search engines update their records to the new URL. 302 is a temporary redirect — clients should keep using the original URL for future requests. For SEO, 301 passes link equity; 302 does not.

What causes a 500 Internal Server Error?

A 500 error means something went wrong on the server. Common causes include unhandled exceptions in application code, database connection failures, file permission issues, and misconfigured server settings. Check server logs for the specific error.

A soft 404 is a page that returns a 200 status code but displays 'page not found' content. Search engines like Google detect soft 404s and may penalize them. Always return an actual 404 status code for pages that don't exist.

HTTP Status Codes Cheat Sheet: Every Code Explained

🌐

Try HTTP Status Codes

Free, no signup →