Metric Measurement

Online Ruler cm: Measure Centimeters on Your Screen

How to use the metric centimeter ruler mode to measure small objects, craft components, and design assets at actual physical size.

Open Centimeter RulerMillimeter Mode (mm)

Centimeter Screen Scale & Metric Divisions

In our online centimeter ruler, numbered major tick marks represent each full centimeter (1 cm, 2 cm, 3 cm, etc.). In between, the scale is subdivided into 10 equal millimeter increments, with a medium-length tick highlighting the half-centimeter (5 mm / 0.5 cm) mark.

1 cm = 10 mm
1 cm = 0.393701 inches
1 inch = 2.54 cm

How to Measure in Centimeters

  1. Open the ruler and ensure cm is highlighted in the unit selector toolbar.
  2. Align the left or top edge of your physical item against the "0" mark at the ruler origin.
  3. Read the closest numbered centimeter mark, then count the smaller tick marks for decimals (e.g., 4 major ticks plus 3 minor ticks = 4.3 cm).
  4. Click on the ruler scale to drop an exact measurement guide with live decimal centimeter tracking.

Common Real-World Objects for Centimeter Verification

Standard Bank / ID Card

Length: exactly 8.56 cm (85.60 mm). Width: exactly 5.40 cm (53.98 mm).

Standard US Dollar Bill

Length: 15.60 cm (6.14 inches). Width: 6.63 cm (2.61 inches).

Euro 50 Note

Length: 14.00 cm. Width: 7.70 cm.

Standard AA Battery

Length: 5.05 cm. Diameter: 1.45 cm.