Screen Size Calculator — TV & Monitor Dimensions

Enter a diagonal and aspect ratio to get width, height, and area in inches and centimeters, plus PPI from resolution.

—Width
—Height
—Area
—PPI

How this conversion works. Width and height come from the Pythagorean theorem applied to the aspect ratio: width = diagonal × w⁄√(w²+h²); PPI divides the diagonal pixel count by diagonal inches. Methodology shown inline.

How to use

  1. Enter the diagonal size in inches.
  2. Pick the aspect ratio (16:9 for most TVs and monitors).
  3. Optionally add resolution to get PPI; read width, height, and area.

Frequently asked questions

How do you get width and height from a diagonal?

Pythagoras: for ratio w:h, width = diagonal × w/√(w²+h²). A 55″ 16:9 TV is 47.9″ wide and 27.0″ tall — before the bezel.

How is PPI calculated?

PPI = √(horizontal² + vertical² pixels) ÷ diagonal inches. A 27″ 4K monitor is 163 PPI; the same panel at 1080p is 82 PPI.

Is a 32:9 ultrawide bigger than two 16:9 monitors?

A 49″ 32:9 panel has exactly the width and height of two 27″ 16:9 panels side by side (identical pixel pitch at matching resolutions).

Is my data sent to a server?

No. All geometry runs in your browser.

Last updated

Powered by maratool