July 13th 2026 - OS Level Fingerprinting In the Browser

OS level fingerprinting identification with JavaScript Math API

Browsers on different OSes use different libraries to evaluate math formulas. If you run the following code you get different results on different OSes, effectively fingerprinting that information regardless of what your User-Agent says.

Math.tanh(0.8)

Output

0.6640367702678491 genuine Linux Chrome (glibc)
0.664036770267849 genuine macOS Chrome (libsystem_m)
0.6640367702678489 genuine Windows Chrome (UCRT)

Source