Which computer details are hidden from websites?

Websites can sometimes tell what browser and screen you use, but they cannot freely open your computer and inspect everything on it. The exact details they can see depend on your browser, privacy settings, and any permissions you grant.

Use System Info to check the computer details your browser can report, then compare them with Browser Info to see browser features and privacy information. This will help you separate information a website may receive from details that stay on your device.

Check what your browser can show

1. Open System Info and review the processor, graphics, screen, battery, and network details it reports. Some information may be missing because browsers do not expose every hardware detail.
2. Open Browser Info and review the browser version, engine, permissions, privacy, codecs, and supported features.
3. Compare those results with your computer's own settings. A website sees information through the browser, so it may receive less detail than the operating system knows about the device.
4. Check site permissions in your browser. Review camera, microphone, and location access for sites you use, and remove permission from sites that do not need it.

The two tools show information available to your browser in this session. They are not a complete inventory of your computer, and another browser or privacy configuration may report different details.

What the result means

A site can see basic browser and display details

A website can usually learn which browser is making a request, along with some details such as the browser's language, time zone, and the size of the browser window or screen. These details help websites display pages correctly. A website's server also receives your public IP address when your browser connects to it. That address can suggest a general location, but it does not normally identify your exact street address.

Browser privacy protections can reduce or standardize some information. Other sites may combine several small details to recognize a browser, a process often called fingerprinting. The details available are not necessarily the same on every browser or device.

Your exact RAM amount may be hidden

Browsers provide websites with only a rounded hint about RAM size, not the computer's exact installed memory. System Info may therefore show a broad estimate or omit a detail that you can find in your operating system. A website should not be treated as a reliable way to check the exact RAM installed in a computer.

Websites do not get a full hardware or file inventory

A normal webpage cannot freely read hardware serial numbers, browse your folders, open your documents, or list every installed program. The browser restricts that kind of access. Some browser features can expose limited information about connected devices, but access is constrained and may require an action or permission from you.

There are exceptions to the idea that details are completely unknowable. A site may infer information from how your browser behaves, or learn details you choose to provide by uploading a file or connecting a device. Avoid sharing sensitive files or granting permissions unless the site needs them.

Camera, microphone, and location access are permission-based

A website that uses your camera or microphone must ask the browser for permission. Location access also requires permission where the browser and device support it. A permission can let a site use that particular feature, but it does not give the site unrestricted access to your computer.

If a site asks for access unexpectedly, deny it. If you already allowed it, remove the permission in the browser and check the operating system's privacy settings as well.

How to limit what websites can access

1. Remove permissions a site does not need. Open the site's permissions from the icon beside the browser address bar, then block camera, microphone, or location access if it is not required. You can review saved site permissions in your browser's privacy or site settings.
2. Check operating system privacy controls. In Windows 11, open Settings › Privacy & security, then review Camera, Microphone, and Location. On a Mac, open System Settings › Privacy & Security and review Camera, Microphone, and Location Services. These controls limit which apps, including browsers, can use those features.
3. Use a browser's privacy protections. Review its tracking protection and fingerprinting settings. Stronger protection can reduce identifying details, but may also affect how some sites work. It does not hide your public IP address from a site's server.
4. Do not assume private browsing hides your device. Private or incognito windows mainly limit what is saved in the browser after the session. The websites you visit can still receive connection and browser information.
5. Review uploads and device connections. Before choosing a file, check that it is the intended file and that it does not contain information you do not want to share. Disconnect devices or stop sharing them when you are done.

Why one website may see more than another

Browsers expose information through different features, and their privacy settings can change what is available. Some information also depends on the operating system and device. For example, Battery Meter and Charger & Cable Test appear only when a browser reports battery information, which is more common on laptops, tablets, and phones than desktop computers.

A browser test can show what the current browser makes available, but it cannot prove exactly what every website collects or how a site uses information after receiving it. For a closer look at browser details specifically, see How to see what browser information sites can access.

System Info and Browser Info run in your browser, so their results are a practical check of what this device and browser expose in the current session.