Volume Converter
Convert between different units of volume and capacity.
Quick Examples
Volume Conversions
Common Conversion Factors
1 Liter = 1000 mL
1 Cup = 236.6 mL
Volume Units
| Unit | Liters | US Fluid Ounces |
|---|---|---|
| Cubic Meter | 1000 | 33,814 |
| US Gallon | 3.785 | 128 |
| Quart | 0.946 | 32 |
| Pint | 0.473 | 16 |
| Cup | 0.237 | 8 |
| Fluid Ounce | 0.0296 | 1 |
US vs Imperial
Imperial gallon (UK) = 4.546 L vs US gallon = 3.785 L. Always verify which system you're using.
What Is Volume?
Volume is the amount of three-dimensional space something occupies — a liquid, a gas, or a solid. The SI base unit is the cubic meter (m³): the space inside a cube one meter on each side. For everyday amounts we use the liter (L), defined as exactly one cubic decimeter (dm³), so 1 L = 1,000 mL = 1,000 cm³.
Volume and capacity are often used interchangeably, but strictly, capacity is what a container can hold while volume is the space something takes up.
Key Conversion Formulas
1 US gal = 4 qt = 8 pt = 16 cups = 128 fl oz
1 cup = 16 tbsp = 48 tsp · 1 tbsp = 3 tsp
Volume Unit Groups
- Metric: cubic meters, liters, milliliters — powers of ten, used worldwide and in all science.
- US customary: gallons, quarts, pints, cups, fluid ounces, tablespoons, teaspoons — American cooking, fuel, and commerce.
- Imperial (UK): the same names as the US units but larger — an imperial gallon is about 20% bigger than a US gallon.
- Cooking: cups, tablespoons, teaspoons — recipe units with fixed relationships (1 cup = 16 tbsp, always).
- Industrial: cubic feet, cubic yards, and oil barrels (42 US gallons) — construction and fuel.
US vs Imperial: Same Names, Different Sizes
The warning above deserves a full comparison, because the gap is large enough to ruin a recipe or a fuel calculation:
| Unit | US | Imperial (UK) |
|---|---|---|
| Gallon | 3.785 L | 4.546 L |
| Quart | 0.946 L | 1.137 L |
| Pint | 0.473 L (16 fl oz) | 0.568 L (20 fl oz) |
| Fluid ounce | 29.57 mL | 28.41 mL |
| Cup | 236.6 mL | 284 mL (metric cup: 250 mL) |
A UK recipe calling for "a pint" means 568 mL, not the US 473 mL. Always match the country your recipe or label comes from.
Step-by-Step: Converting 2 Cups to Milliliters
- Step 1 — Identify the system: use the US cup (236.588 mL) unless the recipe is British or metric.
- Step 2 — Multiply: 2 × 236.588 = 473.176 mL.
- Step 3 — Round for the kitchen: about 473 mL — recipes rarely need more precision.
- Step 4 — Cross-check: 2 cups = 16 fl oz, and 16 × 29.574 = 473.2 mL. Both paths agree.
Worked Examples
Example 1: Scaling a recipe
A recipe needs 1.5 cups of milk: 1.5 × 236.588 = 354.9 mL — call it 355 mL. If your measuring jug is metric, read the mL scale directly.
Example 2: Fuel tank capacity
A 10-gallon fuel tank holds 10 × 3.78541 = 37.85 liters. Going the other way, a 50-liter tank is 50 ÷ 3.78541 ≈ 13.2 US gallons.
Example 3: Concrete for a project
You need 1 cubic meter of concrete: 1 m³ = 35.31 ft³, or about 1.31 cubic yards. Supply yards quote in cubic yards, so convert before you order.
Common Mistakes
- Using a US cup for a UK recipe (or the reverse): the 20% size gap ruins delicate baking.
- Confusing fluid ounces with weight ounces: a fluid ounce is volume (29.57 mL); an ounce is weight (28.35 g). They only match for water.
- Assuming a metric cup is a US cup: a metric cup is 250 mL vs 236.6 mL for the US cup — many international recipes mean the metric one.
- Dry vs liquid pints: a US dry pint is larger than a US liquid pint — produce is often sold by dry measure.
Oil Barrels and Other Bulk Units
Some industries use their own volume units. An oil barrel is 42 US gallons (about 158.99 L) — a legacy of the 19th-century oil trade — while a US dry barrel is 115.6 L and a UK barrel is 163.66 L. In construction, the cubic yard rules: 1 yd³ = 27 ft³ = 764.55 L. A cord of firewood is 128 ft³ (3.62 m³), and a board foot of lumber is 1/12 ft³ (2.36 L).
For these, always confirm which barrel or yard a quote means — suppliers in different countries default to different ones.
Scaling Recipes Up and Down
Recipe scaling is the most common volume conversion in home kitchens. A recipe for 4 servings calls for 2 cups of stock (473.2 mL). To serve 10, multiply by 2.5: 5 cups, or 1,182.9 mL — about 1.18 L. Working in milliliters makes the scaled amount easier to measure in a metric jug.
The reverse direction: a 1-liter carton of stock is 4.227 US cups, so a recipe needing 1 cup uses just under a quarter of the carton. When scaling, convert once to the unit you will measure in, then multiply — converting after scaling doubles the rounding error.
Bottle Sizes: A Hidden Volume Lesson
Wine and spirits bottles are named volumes in disguise. A standard bottle is 750 mL; a magnum holds 1.5 L (two bottles), a jeroboam 3 L (four bottles), and a methuselah 6 L (eight bottles). Beer follows its own tradition: a US pint glass holds 16 fl oz (473 mL) while a UK pint glass holds 20 fl oz (568 mL) — the same glass name, different pour, echoing the US-vs-imperial gap above.
Frequently Asked Questions
How many liters are in a gallon? 3.78541 liters in a US gallon; 4.54609 liters in an imperial (UK) gallon.
How do I convert cubic meters to liters? Multiply by 1,000. A cubic meter is 1,000 cubic decimeters, and a liter is one cubic decimeter.
How many cups are in a liter? About 4.227 US cups (1,000 ÷ 236.588).
Does temperature change volume conversions? The conversion factors assume standard conditions. Liquids expand slightly when heated, so it matters for precise lab work — not for cooking.
What are the different barrel sizes? An oil barrel is 42 US gallons (about 159 L); US dry and liquid barrels and UK barrels all differ — always specify the type.