HTTP request headers
Every request your browser makes carries headers: the User-Agent, accepted languages and content types, client hints such as Sec-CH-UA, and fetch metadata like Sec-Fetch-Site. Servers use them for content negotiation, security decisions and analytics.
Proxies and CDNs may add or change headers, so this page is also a quick way to see what actually reaches a web server from your connection.
よくある質問
Why don't you show cookies?
Cookie and Authorization headers can contain session secrets, so we never display or log them.
What are client hints?
Sec-CH-UA headers are a structured, privacy-preserving replacement for the user agent string in Chromium browsers.