The basic unit for length in the metric system of measurement is the metre (m).

For measuring the lengths of short distances and objects, rulers can be used, using suitable units from the table below.

The commonly used units are millimetres, centimetres, metres and kilometres.

Unit
Convert to
Action
millimetres (mm)
cm
÷ 10
m
÷ 1000
km
÷ 1 000 000
centimetres (cm)
mm
× 10
m
÷ 100
km
÷ 100 000
metres (m)
mm
× 1000
cm
× 100
km
÷ 1000
kilometres (km)
mm
× 1 000 000
cm
× 100 000
m
× 1000