What are HTTP response headers?

HTTP response headers are crucial components of the Hypertext Transfer Protocol (HTTP) and are responsible for conveying additional information about the server's response to a client's request (so between web servers and web browsers). The HTTP header fields are composed by a list of strings which include the HTTP status code (such as 200 OK, 404 Not Found, 403 Forbidden), server type (such as Apache or Nginx), content type (such as text/html) and character encoding.

What can I do with HTTP response headers information?

With this tool you can view the HTTP response headers of any URL, our tool will perform a HTTP GET request on the specified URL and then it will capture the HTTP response headers sent from the website's server to our client. This information is useful to check the HTTP response code of an URL to find out if it returns a 200 (all fine), 301 (moved permanently to another location) or a 404 (not found) status code, and thus troubleshoot bad HTTP status codes such as 404 errors to avoid search engine indexing problems.

Example HTTP response headers for amazon.com

A comprehensive list of HTTP status codes