Two monitors can share the same resolution yet look very different, because sharpness depends on how densely those pixels are packed. Pixels per inch, or PPI, measures that density: it is the number of pixels along each inch of the screen, calculated from the resolution and the diagonal size. A small high resolution screen has a high PPI and looks crisp, while the same resolution stretched across a very large screen has a lower PPI and looks softer. This calculator computes PPI from horizontal pixels, vertical pixels and diagonal size, and also reports the pixel pitch, which is the physical size of one pixel. Both numbers help when comparing monitors for text work, photo editing or gaming, where sharpness matters as much as size.
Quick Answer: Enter the horizontal resolution, vertical resolution and diagonal size in inches, then click Calculate PPI for density and pixel pitch.
Free Online Tool
Monitor PPI Calculator
Sharpness from resolution and diagonal size, in pixels per inch.
How to Use the Monitor PPI Calculator
- Find your monitor’s native resolution, such as 1920 by 1080, from its specifications or display settings.
- Find the diagonal screen size in inches, measured corner to corner across the display area only.
- Enter both values into the calculator, taking care not to include the bezel in the size.
- Click Calculate PPI to see the pixels per inch and the pixel pitch in millimetres.
- Compare the result with other monitors you are considering, at the viewing distance you actually use.
Key Features
- PPI calculation from the diagonal pixel count, using the same geometry as the screen itself.
- Pixel pitch reporting in millimetres, giving a physical sense of pixel size.
- Support for any resolution and size, from laptop screens to large desktop displays.
- Two decimal precision, enough to distinguish close contenders without false precision.
- Instant local calculation, useful while browsing monitor specifications.
Best Practices and Tips
- For text work, higher PPI generally means crisper letters, but scaling settings also affect how large text appears.
- Compare PPI at your real viewing distance. A television viewed from a sofa needs far less density than a monitor viewed at arm’s length.
- Do not confuse PPI with resolution alone. A larger screen with the same resolution always has a lower PPI.
- Check the panel’s native resolution, since running a screen below native resolution reduces effective sharpness regardless of PPI.
Common Mistakes to Avoid
- Measuring the diagonal including the bezel, which inflates the size and understates the PPI.
- Assuming a 4K label guarantees sharpness, when a very large 4K screen can have a lower PPI than a smaller high resolution monitor.
- Comparing PPI figures computed from different size units, such as mixing inches and centimetres in the same calculation.
Frequently Asked Questions
How is PPI calculated?
The diagonal pixel count is found with Pythagoras: the square root of the horizontal pixels squared plus the vertical pixels squared. Dividing that diagonal pixel count by the diagonal screen size in inches gives pixels per inch. Pixel pitch is simply twenty five point four millimetres divided by the PPI.
What PPI is good for a monitor?
Around ninety to one hundred PPI is typical for a standard desktop monitor and looks fine at normal viewing distance. Above about one hundred and ten PPI, text looks noticeably crisper, and laptop screens often exceed one hundred and fifty PPI because they are viewed closer and are smaller.
Is higher PPI always better?
For sharpness, yes, but higher PPI also makes interface elements smaller unless scaling is increased, and it demands more graphics power at the same screen size. The best choice balances density, viewing distance and the scaling behaviour of your operating system.
What is pixel pitch?
Pixel pitch is the centre to centre distance between adjacent pixels, usually given in millimetres. It is the inverse of PPI expressed physically: a higher PPI means a smaller pitch, and a smaller pitch means finer detail on screen.