Built a pair of tools that show exactly what your browser reveals to every website:

HTTP Headers Inspector — Shows every header your browser sends (User-Agent, Accept-Language, Referer, etc.) with risk ratings for each one: http://5.78.129.127/headers

Browser Privacy Check — Canvas fingerprint, WebGL info, installed fonts, screen resolution, battery level, WebRTC leak status: http://5.78.129.127/privacy-check

Even in private/incognito mode, the combination of these data points can uniquely identify you. The canvas fingerprint alone is different for almost every device.

Both run entirely client-side — no data is stored or transmitted.

Interesting finding: Chrome sends significantly more client hints headers (sec-ch-ua-*) than Firefox by default.