Where is 2 cm on a ruler?

Quick Answer

2 cm on a ruler is exactly on the 2 cm line.

The red marker shows 2 cm position on a metric ruler. This is exactly 2 centimeters.

Centimeters on a Ruler


  Ex.: 1, 2.5, 3.5, 10, 15.5
2 cm on a ruler
2 cm on a ruler
exactly on the 2 cm line

How to read cm on a ruler

A metric ruler is numbered in centimeters (cm): the tallest lines are the whole-centimeter marks. Each centimeter is split into 10 millimeters, so the single medium-length line halfway between two cm marks is 0.5 cm (5 mm), and the nine short lines are the individual millimeter steps. So 1 cm = 10 mm.

  • Whole centimeters — the tallest, numbered lines (1, 2, 3 … cm).
  • 0.5 cm mark — the taller line in the middle of each centimeter (e.g. 3.5 cm).
  • Millimeter steps — the short lines; each is 0.1 cm past the last cm line.
  • Reading a value — for 3.5 cm, find the 3 cm line then go to the half mark just after it.

To read a decimal centimeter value, the whole number is the cm line and the first decimal is how many millimeters past it: 3.5 cm → 3 cm + 5 mm. A whole number like 1 cm sits exactly on a numbered line.