What Is My Browser, Screen Size and Device?
Support teams often ask which browser, version and device you use. Here is everything your browser reveals about itself, in one table you can copy and send.
This page only reads information your browser already has. Nothing is sent or stored.
What each item means
- Browser and operating system. Read from your browser’s user agent text. Some browsers shorten or hide parts of it, so treat the version as a good guide rather than exact.
- Screen size. Your screen in CSS pixels, the units web pages use, and in physical pixels. The pixel ratio is how many physical pixels make one CSS pixel; phones and sharp laptop screens are often 2 or 3.
- Browser window. The size of the visible page area right now. It changes as you resize or rotate.
- Colour depth. How many bits of colour the screen reports.
- Language and time zone. The languages and time zone set in your browser or device.
- Dark mode and reduced motion. Your preferences, which sites can use to adapt.
- Connection type. A rough estimate from the browser where it is available. It is not a speed test; use the speed test for real numbers.
When you need these details
- Reporting a bug or asking for help: the browser, version and device type are the first things support needs.
- Building or testing a website: your window size and pixel ratio show how pages will lay out for you.
- Checking that your browser is up to date: compare the version with the latest release of your browser.
Why some items say “not shared”
Browsers choose what to reveal. For example, Firefox and Safari do not share the device memory figure, and some privacy settings and extensions hide more. That is normal and nothing is wrong.
Privacy
Everything on this page is read from your own browser and shown only to you. CHECKiOX does not receive or store it. To see the public IP address websites see for you, use What is my IP address?
Frequently asked questions
What browser am I using?
The table above shows your browser and version, read from your browser's user agent. Edge, Chrome, Firefox, Safari, Opera and Samsung Internet are recognised.
What is my screen resolution?
The table shows your screen size in CSS pixels and in physical pixels. The physical size is the CSS size multiplied by your pixel ratio.
What is a user agent?
It is a line of text your browser sends to websites that names the browser, version and device type. The full text is shown at the bottom of the table.
Is this information sent to CHECKiOX?
No. The page reads it from your browser and displays it to you. Nothing is sent or stored.
Why does the window size change?
The browser window row shows the visible area right now, so it updates when you resize the window, rotate your phone or change the zoom level.
Related tools and guides
- What is my IP address?: your public address.
- Internet speed test: measure your connection.
- IPv6 test: does your connection support IPv6.
- All tools: every CHECKiOX tool in one place.