Dot Pitch Calculator
Enter a screen's pixel density (PPI) to get its dot pitch in millimetres — the spacing between neighbouring pixels — and see why a smaller pitch means a sharper picture.
Pitch from pixel density
Enter the pixels per inch and the calculator returns the dot pitch in millimetres using dotPitch = 25.4 / PPI.
Smaller is sharper
A smaller dot pitch packs pixels closer together, so detail looks crisper — most desktop monitors sit around 0.2 to 0.3 mm.
What is dot pitch?
The spacing between pixels
The dot pitch calculator turns a display's pixel density into the physical distance between neighbouring pixels. Dot pitch is the centre-to-centre spacing of the dots (or pixels) on a screen, measured in millimetres: the tighter that spacing, the more pixels fit into each inch and the finer the detail the screen can show. Because there are exactly 25.4 millimetres in an inch, dot pitch is just that inch divided across the pixels packed into it — so a higher pixels-per-inch (PPI) figure always means a smaller pitch. It is the number behind how sharp a monitor, phone, or TV looks at a normal viewing distance.
Enter a display's pixel density in PPI to get its dot pitch in millimetres instantly.
Dot pitch is one inch — 25.4 millimetres — divided by the number of pixels packed into that inch.
dotPitch = 25.4 / PPIThe 25.4 is fixed — it is simply the number of millimetres in an inch. As the pixel density climbs, the same inch is shared between more pixels, so the spacing between them shrinks. That inverse relationship is the whole idea: double the PPI and you halve the dot pitch.
Suppose a monitor has a pixel density of 109 PPI (a common figure for a 27-inch 1440p display).
Start with the inch
One inch is 25.4 mm — the fixed conversion factor at the top of the formula.
Divide by the pixel density
25.4 / 109 — share that inch across the 109 pixels packed into it.
Read the dot pitch
The result is about 0.2330 mm — the centre-to-centre spacing between neighbouring pixels.
The dot pitch tells you how finely a display resolves detail. A smaller pitch means pixels sit closer together, so edges look smoother and text looks crisper — which is why a smaller number is better. Most desktop monitors land somewhere between roughly 0.20 and 0.30 mm; the 0.233 mm of a 109 PPI screen is typical of a sharp desktop panel, while high-density phone screens push the pitch far lower (a 326 PPI "Retina" display is only about 0.078 mm). Whether a given pitch looks pixelated also depends on how close you sit: a TV viewed from across a room can have a much larger dot pitch than a phone held at arm's length and still look perfectly sharp, because the eye can no longer separate the individual pixels. The figure is therefore best read together with the typical viewing distance rather than on its own.
The formula is exact, but a couple of practical points are worth keeping in mind.
Square pixels and the inverse of PPI
Dot pitch is simply the inverse of pixel density — 25.4 divided by PPI — so it carries the same assumptions. It treats pixels as square and evenly spaced, which holds for almost all modern flat-panel displays but not for older shadow-mask or aperture-grille CRTs that quoted pitch differently. The figure describes how closely pixels are packed; whether that looks sharp to you also depends on viewing distance and your eyesight.