Privacy Guide

What Information Does Your Browser Share?

Your browser is surprisingly talkative. Here is everything it tells websites about you — and what you can do about it.

What information does your browser share with websites?

Your browser shares your IP address, user agent string (browser + OS), screen resolution, viewport size, timezone, language preferences, installed plugins, WebGL renderer (GPU), fonts, touch support, cookie settings, Do Not Track status, and connection type — all without asking permission.

Data Sent With Every Request (HTTP Headers)

Your browser shares your IP address, user agent string, preferred languages, compression support, cookies, and referrer URL with every single web request — before any page content loads.

These headers are sent automatically and cannot be disabled without breaking web functionality:

IP Address: Your network address, revealing location and ISP

User-Agent: Browser name, version, and operating system

Accept-Language: Your preferred languages (e.g., en-US, nb-NO)

Accept-Encoding: Compression formats you support (gzip, br)

Cookie: Any previously stored cookies for that domain

See all the headers your browser sends with our HTTP headers checker .

What your browser is sharing right now

Instead of a generic list, here are the actual hardware and network signals this page can read from your browser without asking for any permission.

Data Accessible via JavaScript

Once a page loads, JavaScript can access a much broader set of data:

See all of this data live: browser details , screen size , timezone , GPU/WebGL info .

How This Enables Tracking

Individually, each data point seems harmless. Combined, they create a unique browser fingerprint that can identify you across websites without cookies.

Think about it: how many people share your exact combination of screen resolution + timezone + language + GPU + browser version + OS? The answer is usually very few — often just you.

Learn more about this in our guide on what browser fingerprinting is .

How to Limit Data Sharing

Use a VPN: Masks your IP address and location

Privacy browsers: Brave randomizes fingerprints, Firefox blocks trackers

Browser extensions: uBlock Origin, Privacy Badger, Canvas Blocker

Disable unnecessary APIs: Turn off WebRTC in settings to prevent IP leaks

Regular updates: Keep your browser updated for latest privacy features

For a step-by-step guide, read how to protect your privacy online without being technical .

Frequently Asked Questions

What information does my browser share automatically?

Your browser automatically shares your IP address, user agent string (browser name, version, OS), accepted languages, accepted encoding formats, referrer URL, and cookie data with every HTTP request. JavaScript can additionally access screen resolution, timezone, hardware details, and more.

Can I stop my browser from sharing data?

You cannot stop all data sharing — HTTP headers are required for the web to function. You can reduce it by using privacy browsers (Brave, Firefox), disabling JavaScript (breaks most sites), using VPNs (hides IP), and installing privacy extensions. Each measure adds a layer of protection.

Does incognito mode prevent data sharing?

No. Incognito mode only prevents local storage of browsing history and cookies. Websites still receive all the same HTTP headers, JavaScript data, and IP address in incognito mode. Your browser fingerprint is also still accessible.

What is the most sensitive data my browser shares?

Your IP address is arguably the most sensitive because it reveals your approximate location and ISP. Your browser fingerprint (combination of all data points) is also concerning because it enables tracking across sessions without cookies. WebRTC can leak your private network IP as well.