Volume Converter (litres, gallons, cups)
Convert litres to gallons, gallons to litres, cups, pints, fluid ounces, spoons and more, with US and UK sizes kept apart. Type in either box. Advanced adds more units and batch convert.
Type in either box. Fractions work too, like 1 1/2 or ¾.
Conversion tables
| L | US gal |
|---|
| US gal | L |
|---|
Real-life examples
Tap an example to convert it.
How your volume is converted
Your numbers, step by step. Every volume unit is a fixed number of litres.
- 1
Your volume
10 L
- 2
Find the factor
1 L =
0.2641720524 US gal - 3
Do the sum
10 ÷ 3.785411784 =
2.641721 US gal - 4
Your answer
2.641721 US gal
1 US gal = 3.785412 L
Read more: the formula, a worked example, US vs UK and kitchen measures
The formula
volume in litres = your number × litres in one of your unit
answer = volume in litres ÷ litres in one of the unit you want
litres to US gallons: US gal = L ÷ 3.785411784
US gallons to litres: L = US gal × 3.785411784
litres to UK gallons: UK gal = L ÷ 4.54609
Worked example
10 litres in US gallons: 10 ÷ 3.785411784 = 2.6417205 US gal, about 2.64 gallons. Going back, 2.6417205 × 3.785411784 = 10 L. In UK gallons it is 10 ÷ 4.54609 = 2.1997 UK gal.
Where 3.785411784 comes from: a US gallon is defined as 231 cubic inches, and a cubic inch is exactly 2.54³ = 16.387064 cm³. 231 × 16.387064 = 3,785.411784 cm³ = 3.785411784 L.
US and UK units side by side
| Unit | US | UK (imperial) |
|---|---|---|
| Gallon | 3.785411784 L | 4.54609 L |
| Quart (¼ gallon) | 946.35 ml | 1,136.52 ml |
| Pint (⅛ gallon) | 473.18 ml (16 fl oz) | 568.26 ml (20 fl oz) |
| Cup | 236.59 ml (8 fl oz) | 284.13 ml (old, ½ pint) |
| Fluid ounce | 29.5735 ml | 28.4131 ml |
Kitchen measures
| Measure | Size |
|---|---|
| US cup | 236.59 ml = 16 tbsp = 48 tsp |
| Metric cup | 250 ml |
| US legal cup (food labels) | 240 ml |
| US tablespoon | 14.79 ml = 3 tsp = ½ fl oz |
| Metric tablespoon | 15 ml |
| Australian tablespoon | 20 ml |
| US teaspoon | 4.93 ml |
| Metric teaspoon | 5 ml |
Cups measure volume, not weight. To turn a cup of flour or sugar into grams, use the cups to grams converter, which knows the weight of each ingredient.
Bigger volumes
1 cubic metre is 1,000 litres or 264.17 US gallons. 1 cubic foot is 28.3168 litres (7.48 US gallons). An oil barrel is 42 US gallons, 158.987 litres. An acre-foot (water for 1 acre, 1 foot deep) is 1,233.48 m³.
More converters: unit converter, area converter, speed converter, oz to grams, lbs to kg, Celsius to Fahrenheit, inches to cm, feet to metres, miles to km, pressure, energy and data storage. To find the volume of a box, tank or cylinder from its sizes, use the volume calculator.
US and UK factors are exact by definition (US gallon = 231 in³; UK gallon = 4.54609 L; oil barrel = 42 US gallons), as listed in NIST Handbook 44 and SP 811. Example sizes such as a 50 litre fuel tank are typical, not standards. Checked 11 October 2026.
Common questions
How many gallons are in a litre?
One litre is 0.264172 US gallons, or 0.219969 UK gallons. To turn litres into US gallons, divide by 3.785411784. So 10 litres is 2.64 US gallons, and a 50 litre fuel tank holds 13.2 US gallons or 11 UK gallons.
How many litres are in a gallon?
A US gallon is exactly 3.785411784 litres and a UK (imperial) gallon is exactly 4.54609 litres. So 5 US gallons is 18.93 litres. Type in the right-hand box above, or press swap, to convert gallons to litres. Ten US gallons is 37.85 litres.
Is a UK gallon bigger than a US gallon?
Yes. A UK gallon is about 20% bigger: 1 UK gallon is 1.20095 US gallons. UK pints and fluid ounces differ too: a UK pint is 568 ml and a US pint 473 ml, while a UK fluid ounce is 28.41 ml and a US one 29.57 ml. Pick the right one in the list.
How many ml are in a cup?
A US cup is 236.59 ml. A metric cup, used in Australia and many other countries, is 250 ml. US nutrition labels use a 240 ml cup. The old UK cup was half a UK pint, 284 ml. The US cup, metric cup and others are all in the list.
How many tablespoons are in a cup?
There are 16 US tablespoons in a US cup, and 3 teaspoons in a tablespoon, so 48 teaspoons in a cup. A US tablespoon is 14.79 ml. Metric tablespoons are 15 ml, and Australian tablespoons are 20 ml, which you can choose in Advanced.
How many litres are in a barrel of oil?
An oil barrel is defined as 42 US gallons, which is 158.987 litres, or about 0.159 cubic metres. Oil prices are quoted per barrel, but oil is not usually shipped in actual barrels any more. A cubic metre holds about 6.29 barrels.
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