Volume Converter: Liters, Gallons, Cups, Milliliters

US vs UK gallons

The US gallon (3.785 liters) and the UK gallon (4.546 liters) are different sizes, with the UK version about 20 percent larger. This is why US fuel-economy figures look much worse than UK ones in MPG. A car doing 30 MPG (US) is actually doing 36 MPG (UK) for the same fuel use. Pakistan and most former British colonies use liters today, but old British-era documents may use the UK gallon. Always confirm which gallon is meant when comparing across borders.

The metric cup vs the US cup

The US cup is 236.588 mL (8 US fluid ounces). The metric cup, used in Australia and parts of Europe, is exactly 250 mL. UK recipes sometimes use a "breakfast cup" that is 284 mL. The calculator uses the US cup by default because it dominates English-language recipe writing. If you are following an Australian recipe with US measuring cups, expect to under-pour by about 6 percent.

Cups, tablespoons, and teaspoons

The US kitchen hierarchy is 1 cup = 16 tablespoons = 48 teaspoons. The exact values are: 1 cup = 236.588 mL, 1 tablespoon = 14.787 mL, 1 teaspoon = 4.929 mL. UK tablespoons and teaspoons are slightly larger (17.76 mL and 5.92 mL respectively), but the difference is small enough that recipes work both ways in most cases.

Fluid ounces are a volume, not a weight

"Fluid ounces" measure volume; "ounces" without the "fluid" measure weight. They are not equivalent. One US fluid ounce of water weighs about one ounce, but one fluid ounce of honey weighs about 1.5 ounces, and one fluid ounce of flour weighs about half an ounce. For weight-to-volume conversions of cooking ingredients, you need to know the density.

Liters and the metric system

The liter is the everyday volume unit in metric countries. One liter equals 1000 mL, or 1 cubic decimeter, or 1/1000 of a cubic meter. Soft drinks come in 0.5 L, 1.5 L, and 2 L bottles. Fuel is sold by the liter in most of the world outside the US. Engine sizes are quoted in liters (a 2.0L engine has 2 liters of displacement).

Cubic meters for large volumes

A cubic meter is 1000 liters. It is the standard unit for shipping volumes, water tanks, gas consumption, and concrete. A typical residential water tank holds 1 to 5 cubic meters. A standard 20-foot shipping container holds about 33 cubic meters. Natural gas consumption is sometimes billed in cubic meters.

Imperial pints and quarts

These are intermediate units: 1 US quart = 2 US pints = 4 US cups = 32 fl oz = 0.946 liter. 1 US gallon = 4 quarts. UK pints (568 mL) are larger than US pints (473 mL), which is why British beer measures are bigger. Many older recipes use pints and quarts; converting to liters or cups makes them easier to work with.

Tablespoons in different countries

US tbsp = 14.787 mL. UK and Canadian tbsp = 14.21 mL. Australian tbsp = 20 mL (notably larger). UK teaspoon = 5 mL by official definition. The calculator uses US tablespoons and teaspoons. If a recipe is Australian, mentally treat one of their tablespoons as about 1.33 US tablespoons.

Converting volume to weight for cooking

For water, 1 cup = 237 grams (essentially the same as mL). For flour, 1 cup = about 120 to 130 grams depending on whether it is sifted. For sugar, 1 cup = about 200 grams. For rice (uncooked), 1 cup = about 185 grams. These weights are approximate because density varies. The volume converter handles volume only; for ingredient weight, use a kitchen scale or a dedicated ingredient density chart.