Monitor PPI Calculator
Find the true sharpness of any monitor: pixels-per-inch, total megapixels and dot pitch from just the resolution and diagonal size.
PPI is the honest resolution metric — a 27" 1440p monitor and a 32" 1440p monitor share the same resolution but very different sharpness. PPI collapses size + resolution into "how fine are the pixels".
Use your monitor's spec sheet: native resolution (e.g. 2560×1440) and diagonal in inches (e.g. 27).
How it works
Pixels-per-inch comes from the diagonal in pixels divided by the diagonal in inches:
pixel diagonal = √(w² + h²) · PPI = pixel diagonal ÷ size (inches)
Dot pitch is millimeters per pixel: 25.4 ÷ PPI.
Example
27" 2560×1440: diagonal ≈ 2938 px → 2938 ÷ 27 ≈ 109 PPI. The same resolution on 32" drops to ~93 PPI — visibly softer text.
The math behind it
PPI = √(w² + h²) ÷ size_in · pitch = 25.4 ÷ PPI
Frequently Asked Questions
What PPI do gamers target?
Most desktop players use 92–140 PPI. Beyond ~150 PPI text becomes tiny at default scaling unless you raise OS scaling (which costs GPU performance in games).
Is higher PPI better for FPS?
Sharper pixels help spotting at range, but PPI taxes the GPU: 4K at 27" is beautiful and heavy. Many pros pick 1080p/1440p for raw frame rate instead.
What's a "Retina" density?
Apple's term for ≥ ~250 PPI at typical viewing distance, where the human eye can't resolve individual pixels. Phones run 400+ PPI; desktop "Retina-class" setups are rare.