What is my screen resolution

Resolution, window size and pixel ratio

Screen resolution is how many pixels your screen has, across and down, such as 1920 × 1080. Websites never get that number directly. They get the screen's size in CSS pixels, which your computer or phone enlarges on sharp screens, plus a pixel ratio: how many real pixels make one CSS pixel, as MDN defines it. The big figure above multiplies the two.

• Screen and window Screen is the whole display, taskbar included. Browser window is the space this page fills.
• Pixel ratio and scaling A ratio of 1 is what Windows calls 100% scaling, the 96 DPI baseline in Microsoft's high-DPI guide, so 1.5 is 150%. Zooming the page changes the ratio too; pinch zoom doesn't.
• Color depth Bits per pixel: 24 means 8 each for red, green and blue.
• Gamut and HDR Whether your screen shows wide color and HDR. Browsers don't agree on what these two answers mean, and the HDR test explains what yours means by them.

Why the numbers differ from your settings

• Scaling At 150%, Windows makes everything half again as large, so a 1920 × 1080 screen shows up as 1280 × 720 CSS pixels.
• Rounding On Windows, Chrome rounds the scaled size up to a whole pixel, per Chromium's code: 2560 ÷ 1.5 is 1706.67, which Chrome gives as 1707.
• Page zoom Chrome and Edge count page zoom in the pixel ratio but not in the screen size, per Chromium's code, so at 110% zoom a 1920 pixel wide screen comes out as 2112. WebKit's current code also counts zoom in the ratio, so Safari may do the same. Ctrl+0 resets the zoom.
• Mac scaled modes On a Mac, Chrome gets the "looks like" size from macOS and, on a Retina screen, a ratio of 2. Multiplied, they give the size macOS renders at, which matches the panel only when "looks like" is exactly half its resolution.
• Privacy In Private Browsing, Safari gives the window size as the screen size, WebKit's blog says.

Common resolutions

Screen size in inches

In CSS one inch is always 96 CSS pixels, whatever the screen, MDN's CSS reference notes. So an inch on a web page may not match an inch on your ruler. For the real size, measure the diagonal of the lit area or find it on the spec sheet.

How the screen resolution check works

We use only what any website can see without asking: the screen and window sizes, devicePixelRatio, screen.colorDepth, two media queries and the orientation. None of it leaves your device. The link to the PPI calculator carries your resolution after a # in its address, a part browsers never send to a server, as our privacy page explains.

• Exact or approximate. We call the figure exact only when the pixel ratio is a whole number, the page isn't zoomed, the screen size differs from the window size, and you're not on macOS, whose scaled modes a page can't see. Otherwise it says "about". We round it down, which undoes Chrome's round-up whenever that added less than one device pixel.
• Zoom. Chrome measures the window before zoom and the page after it, per Chromium's code, so when the two widths differ by more than 5%, the page is probably zoomed. An open side panel also widens the gap, and the note under the figure says so.
• Which screen. With two monitors, MDN says, you usually get the one holding the middle of the window.

Browsers don't give websites your refresh rate at all, so the refresh rate test times your screen's frames instead.