DollarWise

Free Screen Size Calculator

October 12, 2026 · 2 min read · By the DollarWise team

How it works

Enter a screen’s diagonal size and aspect ratio and this calculator works out the real width and height of the display in inches and centimeters. Add the resolution to see pixel density (PPI) as well.

Screen Size Calculator

Real width and height from any diagonal and aspect ratio — in inches and cm, with PPI.

100% Free Forever No Sign-up No Credit Card Private — files never leave your browser Unlimited Use

1 Enter the diagonal and aspect ratio

The number screens are sold by — measured corner to corner of the display.

2 Quick-fill a common screen

3 Resolution (optional, for PPI)

🖥️ Screen dimensions

🎉 Free forever. No sign-up. No credit card. No limits.

This calculator runs entirely in your browser — check as many screens as you like while you shop or measure.

Everyday uses

  • Desk planning: check whether a 27" or 32" monitor actually fits your desk or monitor arm before ordering.
  • TV shopping: compare real width and height of 55" vs 65" TVs against your wall or TV stand.
  • Comparing phones and tablets: two devices with the same diagonal but different ratios have different widths — this shows the true size.
  • Sharpness checks: add the resolution to see PPI and judge whether a bigger screen will look less sharp at your viewing distance.

Frequently asked questions

Why do two screens with the same diagonal have different widths? Because the aspect ratio differs. A 27" 16:9 monitor and a 27" 21:9 ultrawide share a diagonal, but the ultrawide is wider and shorter.

Is the diagonal the whole device or just the display? Just the visible display area, corner to corner. Bezels and the outer frame are not included, which is how manufacturers measure too.

What PPI is considered sharp? Around 90–110 PPI is typical for desktop monitors viewed at arm’s length. Above 150 PPI text looks very crisp, and phones often exceed 400 PPI.