LivePrivacyRuns in your browser

What your browser gives away

What can any website learn about you without asking?

See every detail your browser hands to any website without a prompt, from your time zone and fonts to your graphics chip, what each one means, and how to reduce it. Nothing is sent anywhere.

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Updated September 25, 2026

The browser lab listing the time zone, fonts, graphics chip and other details a browser gives any website, each with what it means and how to reduce it

What it measures

Browser and system

Browser, version, operating system, languages and, in Chrome-based browsers, exact versions and device details handed out on request.

Location hints

Your time zone, which says roughly where you are even behind a VPN.

Fingerprints

Installed fonts, how your computer draws text and shapes, and your graphics chip: details that together can recognise a browser without cookies.

Hardware and signals

Screen, cores, memory, touch, battery, device counts, cookie settings, and whether you send Global Privacy Control.

How to use it

Open the lab. It reads everything at once; there is nothing to type and no permission prompt.
Look at the code at the top. It is made from the details below.
Read each detail, what it means, and how to reduce it.
Open the lab again later, or in a private window. If the code is the same, sites could recognise this browser without cookies.

Open the lab

Good to know

It shows what this page can read. Sites can combine it with your IP address, which only a server sees; this page never contacts one.
It does not score how unique you are, because that needs data about many other browsers, which we do not collect.
Font detection checks 40 common fonts, not every font you have.

What we found

We opened the lab twice in each browser on one Mac, with a fresh profile and both loads in one session. Only Firefox with resistFingerprinting changed its code. One session cannot show whether a browser is recognised across visits or sites.

Measured September 25, 2026

Chrome 154

Same code both times

Exact browser and macOS versions on request, the exact chip (Apple M1 Max), battery level, 21 of 40 fonts. No Global Privacy Control.

Brave 153

Same code both times

Global Privacy Control on. Reported 8 cores and 16 GB instead of 10 and 32, and a different drawing code from Chrome's; the chip name was still shown. Both loads were in one session, so this does not show whether Brave's values change between visits or sites.

Firefox 155

Same code both times

Graphics chip generalised to 'Apple M1, or similar', no battery or memory details. Global Privacy Control off by default.

Firefox 155 with resistFingerprinting

New code each time

Time zone reported as UTC, graphics as 'Mozilla', 8 cores, and a different drawing code on every load. Fonts unchanged: all 21 found ship with macOS.

Method: Headless browsers with new scratch profiles, the lab served locally exactly as the site mounts it; the page's own output read after 4 seconds, twice per browser, one tab after the other in the same session. Chrome 154 and Brave 153 over the DevTools protocol, Firefox 155 over WebDriver BiDi.

How-to

Every website can read dozens of details about your browser without asking: your time zone, screen, fonts, graphics chip and more. Together they can recognise your browser again, even after you clear cookies. You cannot hide everything, but you can blend in more.

See what your browser gives away

Open the browser lab. There is nothing to type.
Note the code at the top, then open the lab again tomorrow, or in a private window.
If the code is the same, sites could recognise this browser without cookies.

Reduce it

Keep your browser up to date, so you match millions of other people on the same version.
Turn on Global Privacy Control. Brave sent it by default in our test. In Firefox, turn on "Tell websites not to sell or share my data" in Settings. Some US state privacy laws, including California's, treat it as a request to opt out.
Limit third-party cookies. Safari blocks them by default and Firefox keeps them separate for each site. In Chrome, look for Third-party cookies under Privacy and security in Settings.
Use fingerprinting protections. Safari only lets sites use the fonts that come with the system, and adds noise to fingerprintable features in Private Browsing. Firefox's resistFingerprinting setting (in about:config) reports UTC as your time zone, reports the window size as the screen size, and in our test changed the drawing code on every load, at the cost of some sites behaving oddly. Brave reported less specific hardware details in our test.
Hide your IP address from the sites you visit with a VPN you trust or iCloud Private Relay. The lab cannot show your IP address, because it never contacts a server; every site you visit sees it.

Check again

Open the lab after each change and compare the details and the code.

Check that it's private

This lab runs entirely in your browser and sends nothing anywhere. You don't have to take our word for it:

The browser enforces it. This site's security policy only lets pages talk to lab.hopperlabs.ai. This command shows connect-src 'self':curl -sI https://lab.hopperlabs.ai/labs/browser-gives-away/run | grep -i content-security-policy
Every file is listed with its fingerprint and source commit in privacy.json, so you or your agent can compare them and read the code.
Once the lab has loaded, turn off Wi-Fi: it keeps working, because it needs nothing from the network.

This page sends nothing anywhere. If an AI agent or browser extension is reading your screen, it can see what's shown here.