Cubic Meter Calculator
Find the volume of almost anything in cubic meters (m³): a box or room, a round tank or pipe, or a slab of concrete, soil or mulch. Type the sizes in mm, cm, m, inches, feet or yards. You also get cubic feet, cubic yards, liters and US gallons.
Volume
Cubic feet
35.31
ft³
Cubic yards
1.308
yd³
Liters
1,000
L
US gallons
264
gal
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Shipping cartons? The CBM calculator adds chargeable weight and container fit.
How to calculate cubic meters
The one rule: turn every size into meters before you multiply. Most wrong answers come from mixing units, such as a bed measured in meters with a depth in centimeters.
cylinder: m³ = π × (diameter ÷ 2)² × height
slab: m³ = area (m²) × depth (m)
If you would rather multiply first and convert after, divide the result by the number below:
| All three sizes in | Divide the product by |
|---|---|
| millimeters | 1,000,000,000 |
| centimeters | 1,000,000 |
| inches | 61,024 |
| feet | 35.315 |
| yards | 1.308 |
Example: a raised garden bed is 240 cm long, 120 cm wide and 30 cm deep. In meters that is 2.4 × 1.2 × 0.3 = 0.864 m³, or 864 liters of soil.
Cubic meters of a cylinder, tank or pipe
For anything round, measure the diameter across the widest point and halve it to get the radius. Then multiply π × radius × radius × height.
Example: a water tank 1.2 m across and 1.5 m tall has a radius of 0.6 m. The volume is 3.1416 × 0.6 × 0.6 × 1.5 = 1.70 m³. That is about 1,696 liters or 448 US gallons. Use the inside size if you want what the tank holds, and the outside size if you want the space it takes up.
Pipes work the same way, with the length as the height. A 6 m pipe with a 100 mm inside diameter holds about 0.047 m³, or 47 liters.
Area × depth: concrete, soil and mulch
When you know the area, you only need the depth. A concrete slab of 20 m² poured 10 cm thick needs 20 × 0.10 = 2.0 m³. In US units, a 200 ft² patio at 4 inches deep is 66.7 ft³, which is 1.89 m³ or about 2.47 cubic yards.
The same math runs backward. Divide the cubic meters you have by the depth to see how much area they cover. 2 m³ of mulch spread 5 cm deep covers 40 m², about 430.6 square feet. Loose material like mulch can settle after it is spread, so ask your supplier how much extra to allow.
What 1 cubic meter looks like
- • A cube 1 m (about 39.4 in) on each side.
- • 1,000 liters, or about 264 US gallons.
- • 35.315 cubic feet, or 1.308 cubic yards.
- • About 1,000 kg if it is filled with water.
Shipping cartons instead?
In freight, a cubic meter is called a CBM, and the price depends on more than volume. The CBM calculator adds up many carton sizes, shows the chargeable weight for sea and air, and checks container fit. For unit swaps, see cubic meters to cubic yards and cubic meters to liters.
Frequently asked questions
How do you calculate cubic meters?
Convert every size to meters first, then multiply length × width × height. A room 4 m long, 3 m wide and 2.5 m high is 4 × 3 × 2.5 = 30 m³. For a round shape, use π × radius² × height instead.
What size is 1 cubic meter?
It is a cube 1 meter on each side, about 39.4 inches. It holds 1,000 liters, about 264 US gallons, 35.3 cubic feet or 1.31 cubic yards. Filled with water, it weighs about 1,000 kg.
How is m3 calculated from centimeters or millimeters?
Multiply the three sizes, then divide by 1,000,000 if they are in centimeters, or by 1,000,000,000 if they are in millimeters. A 90 × 90 × 100 cm bulk bag is 810,000 ÷ 1,000,000 = 0.81 m³.
How do I convert cubic meters to square feet?
You need a depth, because cubic meters measure volume and square feet measure area. Divide the cubic meters by the depth in meters to get square meters, then multiply by 10.764. For example, 2 m³ of mulch spread 5 cm deep covers 2 ÷ 0.05 = 40 m², about 430.6 square feet.
How many cubic feet are in a cubic meter?
One cubic meter is 35.315 cubic feet. To turn cubic feet into cubic meters, divide by 35.315. The calculator shows cubic feet, cubic yards, liters and US gallons for every result.