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Burrows Tools

What Is My Screen Size?

This page reports the size of the display your browser is on: the full screen width and height in pixels, the usable area once system bars are subtracted, the device pixel ratio, and the colour depth. Those numbers answer practical questions — what resolution to export a wallpaper at, whether a monitor is really running at its native resolution, what a Retina or HiDPI screen means for image assets, and which breakpoints a design needs to survive. Note the difference between screen size and window size: screen size describes the physical display, while window size describes the browser viewport your CSS actually lays out against. If you are debugging responsive layouts, the window size tool is the one you want. Everything here is read locally and nothing is recorded.

Your screen resolution

Detecting…

In CSS pixels — the units your operating system's display scaling produces.

Width
0
Height
0
Available
—minus system bars
Pixel ratio
—
Physical pixels
—
Colour depth
—
Orientation
—

How to use the what is my screen size

  1. Open the page — your screen dimensions are detected and shown right away.
  2. Compare the total screen size with the available area to see how much system chrome takes.
  3. Check the device pixel ratio to find out whether you are on a HiDPI or Retina display.
  4. Drag the window to another monitor and reload to read that display instead.

Frequently asked questions

What is the difference between screen size and window size?
Screen size is the whole display. Window size is the browser viewport, which is smaller because of the browser's own toolbars and any space the operating system reserves. CSS media queries respond to the window, not the screen.
What is device pixel ratio?
The number of physical pixels the display uses for each CSS pixel. A ratio of 2 means a Retina-class screen packing four physical pixels into the area of one CSS pixel, which is why images need to be exported at 2x to look sharp.
Why does the reported resolution differ from my monitor's specification?
Operating system display scaling changes the logical resolution the browser sees. A 4K monitor at 200% scaling reports 1920x1080 CSS pixels with a device pixel ratio of 2.
Which monitor is measured in a multi-monitor setup?
The one the browser window is currently on. Move the window to another display and reload to measure that one.

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