What is my screen resolution?
Your screen resolution as websites see it, the physical pixels behind it, your display scaling, and the window and viewport sizes, updated as you resize.
Reading your screen…
What websites can read about your screen
Every value in the table is available to any page without asking: screen.width and screen.height, screen.availWidth and availHeight, window.devicePixelRatio, the window and viewport sizes, the color depth, and media queries for wide color and HDR. Sites use them for layout and image sharpness, and fingerprinting scripts collect them as part of a device's description.
What matters more than any single number is whether they add up: the available screen fits inside the screen, the viewport inside the window, and the scale factor matches what the operating system does. Our browser fingerprint test checks those relationships, and the Q&A on screen fingerprinting explains them.
FAQ
What is my screen resolution?
The number at the top of the page: your screen's width and height as your browser reports them to websites. If your display is scaled (125%, 150% and so on, common on laptops), the page also shows the physical pixel count.
Why is it smaller than my monitor's resolution?
Because of display scaling. A 1920 × 1080 laptop screen at 125% reports 1536 × 864 to websites, and at 150% it reports 1280 × 720. Browsers measure in CSS pixels, and the scale factor, the device pixel ratio, turns them back into physical pixels.
What is the device pixel ratio?
How many physical pixels make one CSS pixel. 1 on an unscaled monitor, 1.25 or 1.5 on scaled Windows laptops, 2 on Retina Macs and most phones, 3 on some phones. Websites read it as window.devicePixelRatio and use it to pick sharp images.
What is the difference between the screen, the window and the viewport?
The screen is the whole display; the available screen leaves out the taskbar or dock; the window is the browser including its frame and toolbars; the viewport is the part a web page is drawn in. Each is readable by any website. The viewport sits inside the window and the available screen inside the screen; a maximized window on Windows may overhang the screen edge by a few pixels, which is normal.
Can websites identify me by my screen resolution?
Not by the resolution alone, since millions of screens share each common size, but it is one of the signals every fingerprinting script collects and combines with others. Values that contradict each other (a viewport larger than its window, a phone-sized screen with a desktop browser) stand out more than a rare size does; the browser fingerprint test checks exactly those relationships.
Related free tools
What browser am I using?
Your browser and version, and whether it is up to date.
What is my user agent?
Your User-Agent and Client Hints, and whether they agree with each other.
Browser fingerprint test
A few hundred coherence checks on the browser you open it in.
WebRTC leak test
Whether WebRTC reveals a different IP, and whether your time zone fits your IP.
Clearcote puts this into practice
An open-source Chromium with fingerprint control compiled into the engine. A drop-in for Playwright & Puppeteer.
Free for one browser with GitHub. No card.