HTTP Headers Checker

How to use the HTTP headers checker

1. Enter a web address. Without http:// or https://, HTTPS is used.
2. Keep Follow redirects on to see every response up to the final page, or turn it off to see only the first one.
3. Each response shows its status code, the server’s IP address, the HTTP version, timings and every header in the order it was sent, with a short explanation of the common ones.

GET or HEAD?

GET is what a browser sends, so it shows the headers visitors get. Only the headers are read: the page itself is not downloaded. HEAD asks for the headers alone; most servers answer it like GET, but some send different headers, a different status code or 405 Method Not Allowed. When the two differ, GET is the one that matters.

Reading the status code

• 2xx: success. 200 OK is a normal page.
• 3xx: a redirect to the address in the Location header. 301 and 308 are permanent, 302 and 307 temporary.
• 4xx: a problem with the request, such as 404 Not Found or 403 Forbidden. Some sites also answer 403 to automated checks.
• 5xx: the server failed. 502, 503 and 504 usually mean a proxy or CDN could not reach the site behind it.

Timings

Connect is the time to open a connection, TLS handshake the time until the secure connection was ready, and first byte the time until the server started answering. A slow first byte with a fast connection usually means the page itself is slow to generate. They are measured from this site’s server, so they depend on where it is.

Privacy

The address you enter is sent to this site, whose server makes the request. It sends no cookies or sign-in details, and only connects to public internet addresses. The result is kept for about a minute, so repeating the same check is instant.