Convert length, area and volume

A factor of 100 is enough to go from metres to centimetres. For square or cubic metres, you need to go further.

A length: multiply once

One metre contains one hundred centimetres. A length of 2.4 m therefore becomes 240 cm. The factor applies once because you are converting one dimension. For the reverse operation, divide by one hundred. Always write units beside numbers: a value alone, such as 240, does not say whether it is centimetres, millimetres or another measure.

An area: convert both dimensions

Imagine a square with sides of one metre. Each side measures one hundred centimetres. Its area is therefore 100 × 100 = 10,000 cm², not 100 cm². Consequently, 2 m² equal 20,000 cm². The length factor is squared. The same logic applies to square feet, square kilometres or any other unit of area.

A volume: convert three dimensions

A cube with sides of one metre measures one hundred centimetres in each of three directions. Its volume is 100 × 100 × 100 = 1,000,000 cm³. One litre corresponds to one cubic decimetre: one cubic metre therefore contains one thousand litres. This helps when reading the volume of a pool or water reserve. A pool 8 m long, 4 m wide and 1.5 m deep on average theoretically contains 48 m³, or 48,000 litres.

Preserve measurement precision

Converting a unit does not make a measurement more accurate. A roughly measured length remains approximate even if the calculator displays several decimal places. To prepare a materials purchase, keep unrounded values during calculation, then adapt the final quantity to packaging and expected losses. The BIPM brochure provides reference definitions for SI units and units accepted for use with them.

References

BIPM — International System of Units brochure

Put it into practice

• Meters → centimeters
• Square meters → square centimeters
• Cubic meters → liters

Educational text prepared with AI assistance. The examples use adjustable assumptions and are not personal advice.