Volume Converter

By Suraj GiriUpdated 24 September 2026

This page converts a volume from one unit into another. Every value passes through the cubic metre, the SI unit volume is held in, and volume stays volume: a unit only converts inside its own dimension.

How do you convert a volume between litres, cubic units and gallons?

Pick the unit you have, pick the unit you want, and type the value. The page multiplies by the factor between the two and prints the arithmetic under the result, so the answer and the working are the same object.

1. Choose the unit your value is in. This page opens on the US liquid gallon.
2. Choose the unit you want it in. This page opens on the litre.
3. Type the value, or the value with its units, such as 5 US gal to L. The result and the factor behind it appear together.
4. Read the working. It converts into the cubic metre first and out again, which is the same two lines you would write by hand.

Litres, gallons and cubic metres convert only to other volumes, so for a mass in kilograms or a flow rate per minute, start from the measurement unit converter.

Volume Conversion Table

One row per unit this page offers, each measured against the cubic metre. The last column says whether the factor is a definition or a reading of one.

Worked Examples

The question the bank ranked highest for this page, answered with the working.

Common Volume Conversions

Each US customary or imperial unit on this page against the metric unit nearest it in size, both ways. Exact values print in full; the rest are rounded to 10 significant figures. Select one to load it into the converter.

• 1 in3 = 16.387064 mL
• 1 mL = 0.06102374409 in3
• 1 ft3 = 28.31684659 L
• 1 L = 0.03531466672 ft3
• 1 US gal = 3.785411784 L
• 1 L = 0.2641720524 US gal
• 1 imp gal = 4.54609 L
• 1 L = 0.2199692483 imp gal
• 1 US fl oz = 29.57352956 mL
• 1 mL = 0.0338140227 US fl oz
• 1 US pt = 0.473176473 L
• 1 L = 2.113376419 US pt
• 1 imp pt = 0.56826125 L
• 1 L = 1.759753986 imp pt
• 1 US cup = 0.2365882365 L
• 1 L = 4.226752838 US cup
• 1 US legal cup = 0.24 L
• 1 L = 4.166666667 US legal cup

Where These Factors Come From

Every factor above is read from the knowledge base rather than typed for the page, and every result is worked from those factors. These are the statements it holds for volume.

• One litre is exactly one cubic decimetre, which is 0.001 m3, and one millilitre is one cubic centimetre.
• The US liquid gallon is exactly 231 cubic inches, which is 3.785411784 L. The imperial gallon is exactly 4.54609 L. They are different units and a recipe or fuel figure has to say which one it means.
• When a unit is squared or cubed, its factor is squared or cubed with it. 1 m = 100 cm, so 1 m2 = 10 000 cm2 and 1 m3 = 1 000 000 cm3.
• An exact factor is a definition rather than a measurement. 1 in = 25.4 mm and 1 lb = 0.45359237 kg were fixed by the 1959 international yard and pound agreement, so they never gain another digit.
• How this page reports a result result in the target volume unit; US and imperial measures are listed separately and never averaged

SI prefixes on this page

Which Gallon, and Is a Cup a Cup?

US and imperial measures are listed here as separate units and are never averaged. The gallon, the pint and the fluid ounce each have a US size and an imperial size, and the cup has a customary size as well as the legal one used on nutrition labels.

• A US gallon and an imperial gallon are different sizes, so a recipe or a fuel figure read in the wrong gallon gives the wrong amount.
• The US customary cup and the US legal cup used on nutrition labels are also different sizes. Pick the one the recipe or label means.
• A cubic unit takes the length factor cubed, not once.

The rule behind this factor is the same for every unit - why a squared unit needs a squared factor.

Frequently Asked Questions

Related Conversions

• Length sits in the same measurement group as volume - convert a length between metres and feet.
• Area sits in the same measurement group as volume - convert an area between square metres and acres.
• If you are measuring mass rather than volume, the mass factor table instead.
• If you are measuring volumetric flow rate rather than volume, convert litres per minute into gallons per minute instead.
• If you are measuring temperature rather than volume, convert a temperature between Celsius and Fahrenheit instead.
• If you are measuring parts-per ratio rather than volume, parts per million, billion and trillion instead.

The rest of the family sits on every measurement family in one place.