Screen Resolution Checker
The size of the screen you are on, in the pixels pages are told about and in the pixels the panel really has.
Results
What this tool does
Screen size sounds like one number and is really two. Web pages are told a comfortable, scaled-down figure so that text does not come out microscopic on a dense display; the panel itself holds several times as many dots. This page shows both, along with the shape of the screen, how many megapixels it adds up to and how many colours it can distinguish. The boxes are editable, so you can also check a screen you do not have in front of you.
Formula
real pixels = advertised pixels × pixel ratio ; possible colours = 2^(bits per pixel)
Variables
| Symbol | Meaning | Unit |
|---|---|---|
screen_w | Screen width, in pixels | px |
screen_h | Screen height, in pixels | px |
dpr | Pixel ratio | — |
depth | Bits per pixel | — |
OUT | Screen | — |
PP | Real pixels | — |
AR | Shape (width to height) | — |
MP | Megapixels | — |
OR | Orientation | — |
CC | Colours it can show | — |
Worked example
- Screen width, in pixels1920 px
- Screen height, in pixels1080 px
- Pixel ratio1
- Bits per pixel24
- Screen1920 x 1080
- Real pixels1920 x 1080
- Shape (width to height)16:9
- Megapixels2.07
- OrientationOn its side
- Colours it can show16,777,216
Limitations
- The calculation runs entirely in your browser. The values you type are never sent to a server.
Frequently asked questions
Why are there two different sets of pixels?
Because on a high-density screen one pixel of a web page covers several pixels of glass. The first number is what pages are told, so that text stays a readable size; the second is what the panel actually contains. A phone announcing 393 by 852 may really have 1179 by 2556 dots, three across for every one a page asks for.
Is this the resolution my monitor is set to?
It is the resolution of the screen this window is on, which on a machine with two monitors is not necessarily the one you think. It is also what the system reports after any scaling it applies, so a display set to 150 per cent will announce two thirds of its real width here and make up the difference in the pixel ratio.