Question 1

What is a user agent?

Accepted Answer

The user agent is a text string your browser sends with every request, identifying the browser name, version, rendering engine, and operating system. Websites use it to adapt content — and sometimes to track or fingerprint visitors.

Question 2

What can websites see about my browser?

Accepted Answer

Beyond the user agent, JavaScript APIs expose your screen resolution, language, timezone, hardware concurrency, memory class, touch support, and preferred color scheme. Combined, these details can identify a browser with surprising accuracy.

Question 3

Why does my browser report a different or frozen version?

Accepted Answer

Browsers now intentionally reduce user agent detail to limit tracking. Chrome freezes parts of the version string and moves details to Client Hints, while Safari reports a fixed macOS version — so small mismatches are expected and harmless.

Question 4

What are Client Hints?

Accepted Answer

Client Hints are the modern replacement for the user agent string. Instead of broadcasting everything to every site, the browser shares specific details — platform, architecture, full version — only when a site explicitly requests them.

Question 5

Does this page collect or store my browser information?

Accepted Answer

No. Everything on this page is read by your own browser using standard web APIs and rendered locally. whatsmy.fyi stores nothing, sets no cookies, and keeps zero logs.

What Browser Am I Using?

Frequently asked questions