Free tool
Monitor Size and PPI Calculator
See a monitor’s real width and height, its pixel density (PPI), and whether two of them fit on your desk before you buy.
This free tool converts a diagonal size and resolution into real screen width and height and pixels per inch (PPI), and checks whether two monitors fit the width of your desk. Compare a 24 inch and a 27 inch screen at the same resolution before you decide which one to buy for your desk.
What it does
Converts a diagonal size and resolution into real width, height and pixel density, and checks whether two monitors fit your desk.
Who it helps
Anyone buying a monitor, comparing two sizes, or planning a dual monitor desk.
How to use it
- Set the screen size (diagonal in inches).
- Pick the aspect ratio and resolution.
- Enter your desk width.
- Open the compare panel for a second monitor.
Screen size (diagonal)
Aspect ratio
Resolution
Your desk width (for 2 monitors)
Compare with a second monitor
Second screen size (diagonal)
Second screen aspect ratio
Your monitor
Two of these need about 49 in. Your 48 in desk is too narrow; consider a monitor arm or a smaller second screen.
Second monitor: 24 in 16:9 is 20.9 in wide and 11.8 in tall.
Viewing distance: 20 to 40 inches from your eyes (OSHA). Larger screens sit toward the far end.
What your result means
- Width and height are the screen itself, before the stand and bezel.
- PPI around 90 to 110 reads well at arm’s length. Much higher usually needs display scaling.
- Two monitors wider than your desk: pick smaller screens or a monitor arm. Read the guide
- Keep the screen 20 to 40 inches from your eyes whatever the size. Read the guide
How it works
Width and height come from the diagonal and aspect ratio (Pythagoras). PPI is the diagonal resolution in pixels divided by the diagonal in inches. The dual monitor check adds 1 inch for bezels. Viewing distance follows the Occupational Safety and Health Administration’s (OSHA) 20 to 40 inches; no other distance formula is used.
Sources
- OSHA, Computer Workstations eTool: Monitors (viewing distance)
FAQ
What PPI is good for office work?
Around 90 to 110 PPI works for most people at normal distance; higher looks sharper but may need scaling.
Is 27 inches too big for a small desk?
Check the width result against your desk and the 20 to 40 inch viewing distance.
What size for two monitors?
Two 24 inch 16:9 screens need about 43 inches of desk width.