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Volume Converter

Convert between metric, US liquid, and imperial volume units including litres, millilitres, gallons, quarts, pints, cups, fluid ounces, tablespoons, and teaspoons.

Enter a value to see conversions

About Volume Conversion

Volume measurements vary significantly around the world. The metric system uses litres and millilitres, while the United States maintains its own customary system with gallons, quarts, pints, and cups that differ from their British counterparts. The UK uses imperial units, but they are not the same sizes as US units.

This converter handles 22 distinct volume units across metric, US liquid, US dry, and imperial categories, making it easy to switch between cooking recipes, scientific measurements, fuel capacities, and everyday liquid quantities.

How Volume Conversion Works

All conversions use the litre (L) as the pivot unit. To convert from unit A to unit B, the value is first converted to litres, then from litres to the target unit.

Conversion formula

VTarget value=VSource value×fSource valuefTarget valueV_{\text{Target value}} = V_{\text{Source value}} \times \dfrac{f_{\text{Source value}}}{f_{\text{Target value}}}VTarget value​=VSource value​×fTarget value​fSource value​​

Where V_A is the value in the source unit, f_A is the factor to convert that unit to litres, and f_B is the factor to convert litres to the target unit.

Everyday Volume Examples

UK Pint of Ale

A traditional UK pint equals 568 mL – noticeably larger than a US pint (473 mL). When ordering a pint at a British pub, you receive about 95 mL more beer than in an American bar.

US Gallon of Milk

The standard US gallon milk jug holds 3.785 L. In countries using metric, the same amount is sold as four 1-litre cartons or two 2-litre bottles.

Olympic Swimming Pool

An Olympic pool contains 2,500,000 litres (2.5 megalitres). That is equivalent to about 660,000 US gallons or 550,000 UK gallons.

Wine Bottle

A standard wine bottle holds 750 mL – three-quarters of a litre. This equals approximately 25.4 US fluid ounces or about 5 standard 150 mL glasses of wine.

How to Use the Volume Converter

  1. 1

    Enter the volume value you want to convert in the input field.

  2. 2

    Select the source unit from the dropdown menu.

  3. 3

    The converter instantly displays the result in all major units.

  4. 4

    Expand the Metric, US Liquid, or Other Units sections to see all 22 units.

  5. 5

    Change the source unit at any time – results update immediately.

Conversion Tips

  • ✓

    US and UK gallons are different: 1 US gallon = 3.785 L, while 1 UK gallon = 4.546 L.

  • ✓

    US and UK pints also differ: 1 US pint = 473 mL, 1 UK pint = 568 mL.

  • ✓

    There are two US cup sizes: the customary cup (236.6 mL) used in recipes, and the US legal cup (240 mL) used on nutrition labels.

  • ✓

    US dry units (dry pint, dry quart, dry gallon) are used for measuring solids like berries and grains – they are larger than their liquid counterparts.

  • ✓

    When following a recipe from another country, always check which cup or pint measurement system is used to avoid errors.

Frequently Asked Questions

Why are US and UK gallons different?▼

The US gallon is based on the Queen Anne wine gallon established in 1707, which measured 231 cubic inches (3.785 L). After American independence, the US retained this measure. The UK later standardised the imperial gallon at 10 pounds of water, equal to 4.546 L. Both evolved independently, resulting in two different definitions.

How many millilitres are in a tablespoon?▼

A US tablespoon equals exactly 14.787 mL (three US teaspoons). An Australian tablespoon is 20 mL. In the UK, a tablespoon is typically considered 15 mL for practical cooking purposes.

What is the difference between a US cup and a metric cup?▼

A US customary cup is 236.588 mL, a US legal cup (nutrition labelling) is 240 mL, and a metric cup (used in Australia, Canada, and New Zealand) is exactly 250 mL. Always check which system your recipe uses.

What are US dry units used for?▼

US dry pints, quarts, and gallons are used to measure dry goods traditionally sold by volume, such as berries, apples, and grain. A US dry pint is 550.6 mL – much larger than the liquid pint of 473 mL.

How many litres does a car fuel tank hold?▼

A typical passenger car fuel tank holds 45–70 litres (about 12–18 US gallons). A compact car might have a 40-litre tank, while an SUV can hold 80 litres or more.

Is a fluid ounce the same as a regular ounce?▼

No. A fluid ounce (fl oz) is a unit of volume, not mass. One US fluid ounce equals 29.574 mL. It is called a fluid ounce because it was historically defined as the volume of one ounce (by weight) of water, but they are not directly interchangeable for other liquids.

Conversion factors are based on internationally recognised standards. US customary and imperial units differ; always verify which system a recipe or specification uses.

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