What are HTTP status codes?

Status codes returned by a server, to indicate how a HTTP request has been handled.

Responses are grouped in five classes:

• 100-199 are Informational responses
• 200-299 are Successful responses
• 300–399 are Redirection messages
• 400-499 are Client error responses
• 500-599 are Server error responses

Example:

HTTP/2 301 Moved Permanently
Location: https://northrook.com/new-address

Need more details? Read the Mozilla Developers resource here.