Volume & Capacity Converter
Convert between liters, gallons, cups, ml, fl oz, and more.
Volume and capacity conversions are essential for cooking, chemistry, automotive work, and international trade. The challenge is that two overlapping systems — metric and US customary — use different base units, and some terms (like "pint" and "gallon") mean different volumes in the US versus the UK. Knowing which system a recipe or specification uses can be the difference between a great dish and a failed experiment.
Popular Volume & Capacity Conversions
Standards Note: A Liter Is a Cubic Decimeter
NIST defines the liter as the cubic decimeter and the milliliter as the cubic centimeter, which is why 1,000 mL = 1 L is exact inside the metric system.
Source: SI Units - Volume | NIST
US Customary vs. Metric vs. Imperial
The US customary system uses fluid ounces, cups, pints, quarts, and gallons. The UK (imperial) system uses the same names but different volumes: a UK pint is 568 mL, while a US pint is 473 mL — an 18% difference that matters when following a British recipe or pouring beer. The metric system uses liters and milliliters, which are related by a factor of 1,000. Scientific work always uses metric. Most cooking recipes outside the US use grams (weight) rather than volume, avoiding ambiguity about ingredient density altogether.
Kitchen Volume Conversions
The US measuring cup (240 mL) is the cornerstone of American home cooking. One cup equals 8 fluid ounces, 16 tablespoons, or 48 teaspoons. For baking, weight is more precise than volume — a cup of packed brown sugar can weigh anywhere from 180 to 220 grams depending on how tightly it's packed. For liquids, however, volume is perfectly adequate since water and most thin liquids have a density close to 1 g/mL.
| Unit | Equivalent |
|---|---|
| 1 teaspoon (US) | 4.93 mL |
| 1 tablespoon (US) | 14.79 mL |
| 1 cup (US) | 240 mL |
| 1 pint (US) | 473 mL |
| 1 quart (US) | 946 mL |
| 1 gallon (US) | 3.785 L |
| 1 liter | 33.8 fl oz / 4.2 cups |
Beyond the Kitchen: Fuel and Industrial Uses
Outside the kitchen, volume conversions appear when fueling vehicles, buying paint, or understanding chemical concentrations. The US sells gasoline in gallons, while the rest of the world uses liters. When comparing fuel economy between vehicles sold in different countries, you need to convert both volume and distance units — a European car rated at 6 L/100km is roughly equivalent to 39 mpg. In medicine and chemistry, milliliters are universal: an oral syringe marked in mL is the global standard for dosing liquid medications.
Metric system: units of volume | 4th grade | Khan Academy
Khan Academy walks through metric volume units and gives a fast refresher on how liters and milliliters relate in everyday measuring tasks.
Video source: Khan Academy
Further Reading
Sources & References
- NIST — Units and Conversion Factors — Liters, gallons, cups, and fluid ounce conversions from NIST.