CalcOS

Measurement Tools

Measure physical objects and calculate screen parameters directly on your display. Calibrate our virtual ruler to display actual physical sizes in inches and centimeters, or compute screen aspect ratios and Pixels Per Inch (PPI) density to optimize media layouts and design work.

Measurement Tools Frequently Asked Questions

Common questions and answers regarding our measurement tools calculators and methods.

How do you calibrate an online ruler to show actual size?

Calibrating the ruler requires entering your screen's physical diagonal size in inches. This calculates the physical size of each pixel on your monitor, rendering a ruler that matches physical inches and centimeters.

What is the difference between PPI and DPI?

PPI (Pixels Per Inch) measures the pixel density of a screen. DPI (Dots Per Inch) measures the density of ink dots printed on paper. While similar, they apply to digital vs. printed mediums.

What is the standard widescreen aspect ratio?

The modern widescreen standard is 16:9, which is the default aspect ratio for high-definition television, computer monitors, and YouTube video layouts.