This free online volume converter switches between milliliters, liters, cubic meters, US gallons, and cubic feet. Enter a value, select your source and target units, and get an accurate result for cooking, fuel, or liquid measurement needs.
How to Use the Volume Converter
- Select the unit you are converting from in the "From Unit" dropdown, such as Liter (L) or Gallon (US).
- Select the unit you want to convert to in the "To Unit" dropdown, such as Milliliter (ml) or Cubic Foot (ft³).
- Enter the amount you want to convert in the "Value" field.
- Click "Convert" to see the equivalent volume instantly.
How the Volume Conversion Works
The litre is the reference unit. Your value is multiplied by the "From" unit's size in litres and then divided by the size of the "To" unit. The metric units line up neatly: a litre is the volume of a cube 10 cm on each side, so 1 millilitre equals 1 cubic centimetre (the "cc" used for engines and syringes) and 1 cubic metre holds exactly 1,000 litres.
| Unit | Size in litres | Basis |
|---|
| Millilitre | 0.001 | 1 cm³ |
| Cubic metre | 1,000 | 1 m × 1 m × 1 m, also called a kilolitre |
| US gallon | 3.785411784 | 231 cubic inches |
| Cubic foot | 28.316846592 | 0.3048 m cubed |
Internally the converter rounds the US gallon to 3.78541 L and the cubic foot to 28.3168 L. That only affects the sixth significant digit and has no practical effect on everyday measurements.
Worked Examples
Water tank capacity: a rectangular tank measuring 1.2 m × 1 m × 1 m holds 1.2 m³. Converting cubic metres to litres gives 1.2 × 1,000 = 1,200 litres. If the tank was measured in feet instead, say 4 ft × 3 ft × 3 ft = 36 ft³, then 36 × 28.3168 ≈ 1,019 litres.
Fuel economy from the US: American car reviews quote miles per US gallon. A car rated at 25 mpg covers 25 × 1.609344 ≈ 40.23 km on 3.785 litres, which is about 10.63 km per litre. If the source is British, the gallon is larger (4.54609 L), and 25 mpg works out to only about 8.85 km per litre.
Water bills: many municipal water boards in India bill per kilolitre. One kilolitre is one cubic metre or 1,000 litres, so a monthly use of 18 kL means 18,000 litres.
Common Volume Equivalents
| Value | Equals |
|---|
| 1 L | 1,000 ml = 0.26417 US gal = 0.035315 ft³ |
| 1 US gal | 3.7854 L |
| 1 UK gallon | 4.5461 L |
| 1 ft³ | 28.317 L |
| 1 m³ | 1,000 L = 35.315 ft³ = 264.17 US gal |
| 20 L | 5.2834 US gal |
| 1,000 cc | 1 L |
Points to Watch
- US and UK gallons are different. A UK (imperial) gallon is about 1.2 US gallons. This converter offers only the US gallon, so if a figure comes from the UK, multiply UK gallons by 4.54609 to get litres.
- Volume is not weight. A litre of water weighs about 1 kg, but a litre of cooking oil weighs only about 0.91 to 0.92 kg, which is why oil packed by weight and oil packed by volume are not directly comparable on price.
- Engine sizes in cc are volumes. A 1,500 cc engine has a displacement of 1.5 litres, and a 150 cc motorcycle engine displaces 0.15 litres.
- When working from tank or room dimensions, keep every side in the same unit before multiplying. Mixing feet and inches, or metres and centimetres, is the most common source of large errors.
Frequently Asked Questions
1 US gallon equals approximately 3.785 liters. Set "From Unit" to Gallon (US) and "To Unit" to Liter (L) to verify any amount.
1 liter equals 1,000 milliliters, since the milliliter is defined as one-thousandth of a liter.
A US gallon is 3.785411784 litres, while a UK (imperial) gallon is 4.54609 litres, about 20% larger. Fuel economy and tank figures from the US and the UK are therefore not directly comparable. This converter uses the US gallon.
A cubic metre holds exactly 1,000 litres. It is the same as a kilolitre, the unit many water utilities use for billing.
Yes. One cubic centimetre (cc) is exactly one millilitre. Medicine syringes and engine displacements use cc, and you can treat the number as millilitres when converting.