Convert between milliliters, liters and cubic meters and the US customary teaspoon, tablespoon, fluid ounce, cup, pint, quart and gallon — plus the UK (imperial) gallon.
Each unit is defined as an exact multiple of one SI base unit. We multiply your value by the “from” unit’s factor to reach the base unit, then divide by the “to” unit’s factor. Full floating-point precision is kept throughout; only the displayed result is rounded. The US customary units all derive from the US gallon of exactly 231 cubic inches.
base unit: cubic meter · 1 L = 0.001 m³
1 US gal = 231 in³ = 3.785411784 L · qt = gal/4 · pt = gal/8 · cup = gal/16
fl oz = gal/128 · tbsp = fl oz/2 · tsp = tbsp/3 · 1 UK gal = 4.54609 L
Worked example (default inputs)
2 cup = 473.176473 mL
1 US cup = 8 US fl oz = 236.5882365 mL
1 mL = 1 cm³ = 0.000001 m³
US customary, not imperial
The teaspoon, tablespoon, fluid ounce, cup, pint and quart on this page are US customary units, and they are labeled “US” in the unit list. The UK imperial system uses different sizes: an imperial gallon is 4.54609 liters, about 20% larger than the US gallon, and imperial pints and fluid ounces differ too. Only the gallon is offered in both versions here, so you can compare fuel economy or recipes across the Atlantic without mixing them up. For a trip’s gas bill, the fuel cost calculator works in US gallons.
Cooking conversions
A US cup is exactly 8 US fluid ounces, or 236.5882365 mL. Nutrition labels in the United States use a rounded “legal cup” of 240 mL, and many metric recipes use a 250 mL cup — so if a recipe is from outside the US, check which cup it means. A tablespoon is 3 teaspoons, and 2 tablespoons make a fluid ounce.
Volume versus weight
This converter handles volume only. A cup of flour and a cup of water take up the same space but weigh very different amounts, so converting cups to grams depends on the ingredient’s density. Use the weight converter for grams, ounces and pounds.
Worked examples
Scaling a recipe: halving 1 tablespoon gives 1½ teaspoons, because a tablespoon is exactly 3 teaspoons — see tablespoons to teaspoons. Converting a US recipe for a metric kitchen, 2 cups is about 473 mL; the cups to milliliters table covers the common fractions.
Travel and fuel: a 50-liter tank holds about 13.2 US gallons, and fuel priced per liter can be compared with US prices by multiplying the per-liter price by 3.785. The liters to gallons page shows common tank sizes.
Carry-on liquids: the 100 mL airport limit is about 3.4 US fluid ounces, which is why US rules print “3.4 oz”. Milliliters to fluid ounces covers bottle and can sizes such as 355 mL and 750 mL.