Cubic Meters Calculator

What the cubic meters calculator does

The cubic meter is the volume unit most of the world builds and ships with, so for plenty of jobs it is the number you actually need. This works it out. You give it a length, a width, and a height, and it returns the volume in cubic meters, with a cost if you add a price.

It is the metric workhorse for volume. Below is how it works and where it is the right unit to reach for.

How to use it

1. Enter the length, width, and height, each with its own unit. You can mix metric and imperial freely.
2. Add a price per cubic meter if you want a cost.
3. Press Calculate for the volume, or Reset to clear it.

How the volume is worked out

Volume is the three measurements multiplied, once they are all in meters:

Cubic meters = length × width × height

The calculator converts each measurement to meters first, whatever unit you used, then multiplies them together. The cost, if you add one, is the volume times your price per cubic meter.

Cubic meters and litres

The cubic meter sits in a tidy relationship with the litre, which is part of why metric volume is easy to work with. One cubic meter is exactly 1,000 litres, because a meter is 100 centimeters and a litre is a 10 centimeter cube. So a result in cubic meters is also a result in thousands of litres, no awkward conversion needed.

That makes the unit comfortable across very different jobs. A small volume reads naturally in litres, a large one in cubic meters, and they are the same measure scaled by a thousand. Water, in particular, is simple here: a cubic meter of it is 1,000 litres and weighs about a tonne.

A worked example: a concrete slab

Say you are pouring a slab 5 meters long, 4 meters wide, and 100 millimeters thick.

The thickness in meters is 100 ÷ 1,000 = 0.1 meters. So the volume is 5 × 4 × 0.1 = 2 cubic meters, which is also 2,000 litres.

That is the figure you would order concrete by in most of the world, give or take a little extra for the pour.

Where cubic meters is used

Outside the United States, the cubic meter is the default for almost any sizeable volume. Concrete and bulk materials are ordered by it, shipping and freight space is quoted in it, and water and gas use is often billed by it. If you are working from metric plans or dealing with an international supplier, this is the unit on the paperwork.

Because the calculator takes imperial measurements too, it doubles as a converter: measure in feet and inches, read the answer in cubic meters. For the imperial equivalent, the cubic feet and cubic yards calculators work in those units, with one cubic meter being about 35.3 cubic feet.

Questions people ask

How do I calculate cubic meters?

Multiply length by width by height, with all three in meters. A 5 by 4 by 0.1 meter slab is 2 cubic meters. The calculator converts other units first.

How many litres are in a cubic meter?

Exactly 1,000, since a litre is a 10 centimeter cube and a cubic meter is a 100 centimeter cube.

How many cubic feet are in a cubic meter?

About 35.3, so a cubic meter is a good deal larger than a cubic foot. The cubic feet calculator works in that unit.

Why enter thickness in millimeters?

Because slabs and layers are often specified in millimeters on metric plans. The calculator converts them to meters before working out the volume.

References

A quick note on the numbers. The volume is plain geometry, length times width times height. The conversions to meters, and the fixed relationship that a cubic meter is 1,000 litres and about 35.3 cubic feet, follow the US National Institute of Standards and Technology guide, where a foot is defined as exactly 0.3048 meters.

1. National Institute of Standards and Technology (NIST), Special Publication 811, Guide for the Use of the International System of Units (SI). https://www.nist.gov/pml/special-publication-811