API & Network

HTTP Headers Checker

Inspect response headers of any URL.

100% browser No upload Free forever

URL

Common questions

FAQ

1 Why are some headers missing?

Browsers expose only CORS-safelisted headers to JS. Servers can opt in via Access-Control-Expose-Headers.

Send HTTP requests from your browser.

Look up your public IP and basic info.

Parse a UA string into browser/OS/device.

Resolve A, AAAA, MX, TXT records via DoH.

Convert a cURL command to fetch() code.