How does the 32-bit or 64-bit tool work?

This page works entirely in your browser; nothing is sent to our server.

1. A first guess from your browser's user agent

Every browser sends a short description of itself, called the user agent, with each request. The page reads it:

• If it mentions 64-bit Windows or a 64-bit processor type, the answer is 64-bit.
• If it's a Mac, iPhone or iPad, the answer is 64-bit: Apple devices now only run 64-bit software.
• If it's Windows without the 64-bit markers, or an older 32-bit phone processor, the answer is 32-bit.
• Otherwise, the answer is Unknown.

2. A better answer where the browser offers one

Chrome, Edge and other Chromium-based browsers can report the system's bitness directly. If your browser answers "32" or "64", that replaces the guess.

Limits

Firefox and Safari don't offer the direct answer, so they rely on the guess. Browsers increasingly trim their user agent, so many Android phones show "Unknown". And if you change your browser's user agent, the answer may be wrong.

Last updated: September 29, 2026 (12:46 AM GMT)