Cubic Meter Calculator
Calculate volume in cubic meters, liters, and gallons from length, width, and height measured in meters.
How this calculator works
The calculator multiplies length, width, and height together, with all three measurements entered in meters, to get the volume in cubic meters. It then converts that figure into liters and into US gallons, so you have all three units for the same volume in one place.
Formula: Cubic meters = length × width × height (all in meters). Liters = cubic meters × 1,000. Gallons = cubic meters × 264.172.
Worked example
A space 4 m × 3 m × 2 m:
- Volume: 4 × 3 × 2 = 24 m³
- Liters: 24 × 1,000 = 24,000 L
- Gallons: 24 × 264.172 ≈ 6,340.13 gal
Notes
One cubic meter always equals exactly 1,000 liters. That relationship is a fixed definition, not an approximation, which makes converting between cubic meters and liters simple — just move the decimal point three places.
The gallon figure on this calculator uses the US gallon, at 264.172 gallons per cubic meter. The UK, or imperial, gallon is a different and larger unit, so a volume converted using the US factor will not match a total calculated with the imperial gallon. Check which gallon definition matters for your situation before comparing numbers across sources.
Keep all three measurements — length, width, and height — in meters before multiplying them together. Mixing units, such as entering one dimension in centimeters, will throw off the cubic meter result and everything converted from it.
How to use
Measure length, width, and height in meters and enter all three. The calculator returns the volume in cubic meters, along with the equivalent in liters and US gallons, so you can work with whichever unit your project or supplier uses.
A pure geometry calculation. Always double-check real-world measurements before ordering material.
Frequently asked questions
What's the formula for cubic meters?
Cubic meters = length × width × height, with all three measurements taken in meters. Multiply the three numbers together and the result is the volume in cubic meters.
How do I convert cubic meters to liters?
Multiply the cubic meter figure by 1,000. One cubic meter always equals exactly 1,000 liters, since a liter is defined as one-thousandth of a cubic meter — there's no rounding or approximation involved in that conversion.
How do I convert cubic meters to gallons?
Multiply the cubic meter figure by 264.172 to get US gallons. This calculator uses the US gallon definition; the UK (imperial) gallon is a different, larger unit, so a figure converted with the US factor will not match an imperial gallon total.
Why does the gallon result look different from what I expected?
Check which gallon definition you're comparing against. The US gallon and the UK imperial gallon are different sizes, so a cubic meter volume converts to a different number of gallons depending on which one is used. This calculator uses the US gallon (264.172 gallons per cubic meter).
Estimates only. Verify quantities with your supplier before purchasing.