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Online Scale & Measurement Tool
On-screen ruler with calibration and a comprehensive length unit converter. Measure in cm, inches, mm, and convert between 10 measurement units.
On-Screen Ruler
Current calibration: 96 PPI · 1 cm = 37.8 px · Calibrate for accurate physical measurements
Length Unit Converter
10 cm = 3.937007874 in
10 Centimeters (cm) in All Units
Millimeters (mm)100
Centimeters (cm)10
Meters (m)0.1
Kilometers (km)0.0001
Inches (in)3.9370079
Feet (ft)0.32808399
Yards (yd)0.10936133
Miles (mi)6.2137e-5
Micrometers (μm)100000
Nanometers (nm)100000000
Overview
What this tool does
An on-screen ruler calibrated to your display plus a length unit converter for mm, cm, m, km, inches, feet, yards, and miles.
100% private in-browser processing. Zero cloud uploads.
Tutorial
How to use it
- 1Use the on-screen ruler to measure objects against your screen.
- 2Switch between CM and Inch scales; toggle horizontal / vertical orientation.
- 3Calibrate the ruler with a credit card for accurate physical measurements.
- 4Use the length converter below the ruler to convert between 10 measurement units.
- 5View the all-units table for a complete breakdown.
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