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Online Ruler

Display a real-size ruler in your browser to measure objects. Screen calibration ensures accuracy on any monitor.

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How to Use

Step 1

Calibrate Screen

Calibrate Screen

Calibrate the screen scale using a reference object like a credit card

Step 2

Place Object on Screen

Place Object on Screen

Place the object you want to measure against the ruler on the screen

Step 3

Read Measurement

Read Measurement

Read the length in cm or inches from the ruler markings

Features

cm/inch Toggle

Easily toggle between centimeters and inches for measurement

Screen Calibration

Accurate display on any monitor with reference object calibration

Mobile Friendly

Works on smartphones and tablets too

FAQ

It displays with default values, but calibration is recommended for accurate measurement, especially on monitors with different sizes or DPI.