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Illustration of a pint milk bottle, a gallon container, and a litre bottle filled with water.

Liquids

UK and US gallons, pints, fluid ounces, litres and cubic centimetres

Edit any field; imperial (UK) and US liquid measures stay in sync with fluid ounces, litres, and cubic centimetres. Eight pints to one gallon in each system.

Imperial gallon 4.54609 L; US liquid gallon 3.785411784 L. Each gallon is 8 pints in its own system. 1 L = 1000 cm³.

1 litre of water weighs 1Kg. For UK pints only, a pint of water weighs a pound and a quarter (approximately). For US pints only, a pint's a pound (approximately) :)

Related converters: Cups and Spoons, Weight, and Travel.

How this liquid volume converter works

UK, US, and metric liquid units

Liquid volume is one of the most confusing everyday measurement topics because the same names mean different sizes in the UK and the US. A US pint is smaller than an imperial (UK) pint; a US gallon is smaller than an imperial gallon; fluid ounces differ too. Metric litres and millilitres avoid that branding confusion and are standard on most modern packaging outside the US.

This page synchronises UK gallons, UK pints, UK fluid ounces, US gallons, US pints, US fluid ounces, litres, and cubic centimetres (millilitres) so you can translate a recipe, drinks menu, or datasheet without hunting for the right factor.

Important size differences

  • 1 imperial gallon = 4.54609 litres
  • 1 US liquid gallon = 3.785411784 litres
  • 1 imperial pint = 568.26125 ml
  • 1 US liquid pint = 473.176473 ml

Cubic centimetres and millilitres are the same volume for practical kitchen and medical purposes (1 cm³ = 1 ml of water-density liquid under usual assumptions).

Worked example

A UK pub pint (imperial) is about 568 ml. A US liquid pint is about 473 ml. Pouring a “pint” from an American recipe with UK glassware therefore under-fills the glass if you treat the numbers as identical. Likewise, 1 US gallon ≈ 0.8327 imperial gallons.

When each system appears

Use imperial units for older UK recipes, some pub measures, and British vehicle fuel economy expressed per imperial gallon. Use US customary units for American recipes and US fuel economy (MPG). Prefer litres and millilitres whenever a pack already prints metric — then convert only if you need a customary equivalent.

Common mistakes

  • Assuming “pint,” “gallon,” or “fl oz” are universal sizes.
  • Mixing dry US measures with liquid US measures — this page is for liquid volumes.
  • Using cup sizes here — kitchen cups differ by region; see Cups & Spoons and the cup sizes guide.

FAQs

Is a litre exactly 1,000 ml?
Yes. One litre is 1,000 cubic centimetres / millilitres.
Why do fuel economy pages also list gallons?
MPG depends on which gallon you use. The Travel converter keeps UK and US MPG separate for that reason.

Related: Cups & Spoons, Drink Glasses, Travel.

Last updated: July 2026