Tools
PPI and viewing-distance calculator
PPI is the pixel diagonal divided by the glass diagonal in inches. 1920×1080 on 24 inches is about 91.8 PPI. 2560×1440 on 27 inches is about 108.8. Type a viewing distance in centimeters to see the vertical angle of that picture. The angle is geometry, not a “sit here” rule.
PPI
91.8
Picture height angle
24.1°
Physical picture
20.9 × 11.8 in
Pixel diagonal
2203 px
How PPI and the angle are built
pixel diagonal = √(width² + height²)
PPI = pixel diagonal / diagonal inches
picture height (in) = diagonal / √(aspect² + 1), where aspect = width ÷ height
height angle = 2 × atan((height / 2) / (distance_cm / 2.54)), in degrees
A 24-inch 1080p panel is about 92 PPI. A 27-inch 1440p screen, like my 155 Hz one, is the sharper desk. The FPS monitor page already prints those densities. This tool is the same hypot for a size you type.
Common questions
How do you calculate PPI?
Take the square root of width squared plus height squared, then divide by the diagonal in inches. That gives about 92 PPI for a 24-inch 1080p monitor, 109 for 27-inch 1440p, and 138 for 32-inch 4K.
What is the picture-height angle?
It's how tall the screen looks from where you sit, measured in degrees. It's calculated as 2 × atan((screen height ÷ 2) ÷ viewing distance), and it helps you compare screen sizes at your seating distance.
Does a higher PPI make text sharper?
Yes. Higher PPI fits more pixels into each inch, so text and fine details look crisper. Very high PPI can make text tiny, though, so you may need Windows scaling.
Is 110 PPI the same on a 27-inch and a 49-inch monitor?
Yes, the sharpness is about the same. A 27-inch 1440p monitor and a 49-inch Samsung Odyssey G9 Dual QHD both sit around 110 PPI. The G9 just gives you a lot more horizontal space.
Does the PPI calculator include bezels or curve?
No. It uses the screen's diagonal size from the spec sheet, which measures only the visible picture area.
Ultrawide density notes live on ultrawide vs 16:9. Field of view is a different number: the FOV converter.