Volume Converter
Convert liquid and dry volume measurements between metric and US/UK units. Perfect for scaling recipes, comparing fuel efficiency, or working with international specifications. Type a value and the conversion appears immediately.
How It Works
This volume converter uses the liter (L) as its base unit. Each unit's stored factor is the number of liters it represents. Conversion follows the same two-step algorithm: multiply the input by the source unit's liter-factor, then divide by the target unit's liter-factor.
The liter is a metric unit of volume defined as one cubic decimeter (dm³) — a cube 10 cm on each side. It is not an SI base unit (that honor goes to the cubic meter, m³), but it is accepted by SI for everyday use. 1 m³ = 1,000 liters.
The US liquid gallon (3.78541 L) differs from the imperial gallon (4.54609 L) used in the UK. This tool converts US gallons. The difference matters in real-world contexts: when a US recipe calls for a gallon of liquid or a fuel efficiency is given as miles per gallon, the US gallon applies. A UK car achieving 40 mpg (imperial) is actually more fuel-efficient than a US car rated at 40 mpg (US).
US customary volume units form a nested structure:
1 gallon = 4 quarts = 8 pints = 16 cups = 128 fl oz = 256 tablespoons = 768 teaspoons
Worked example — Scale a recipe from metric to US:
A bread recipe calls for 500 mL of water. How many cups is that?
500 mL = 0.5 L ÷ 0.236588 L/cup = 2.113 cups ≈ 2 cups + 2 tablespoons.
Worked example — Tank capacity:
A car fuel tank holds 60 liters. How many US gallons?
60 ÷ 3.78541 = 15.85 gallons.
Worked example — Medical syringe:
A 10 mL syringe holds how many fluid ounces?
10 × 0.001 L/mL ÷ 0.0295735 L/fl_oz = 0.338 fl oz.
Worked example — Aquarium volume:
An aquarium 90 cm × 45 cm × 45 cm = 182,250 cm³ = 182.25 L = 48.15 US gallons.
Cooking notes: the "cup" in this converter is the US legal cup (240 mL). UK recipes sometimes use an "imperial cup" (284 mL), though UK cooking more commonly uses grams and milliliters. Australia uses a 250 mL cup.
Frequently Asked Questions
How many milliliters are in a liter?
Exactly 1,000 mL per liter. The prefix "milli" means one-thousandth, so 1 mL = 0.001 L. A standard water bottle is 500 mL = 0.5 L.
How many liters are in a US gallon?
1 US liquid gallon = 3.78541 liters. The US gallon differs from the UK imperial gallon (4.54609 L), so always check which gallon is meant in recipes or fuel economy ratings.
How many tablespoons are in a cup?
16 tablespoons per US cup. The chain is: 1 cup = 16 tbsp = 48 tsp = 8 fl oz = 0.5 pint = 0.25 quart = 0.0625 gallon.
What is the difference between a fluid ounce and a regular ounce?
A fluid ounce (fl oz) is a unit of volume: 1 US fl oz = 29.5735 mL. A regular (avoirdupois) ounce is a unit of mass: 1 oz = 28.3495 g. They are different physical quantities — one measures how much space a liquid takes up, the other measures mass.
How many cups in a liter?
1 liter ÷ 0.236588 L/cup = 4.227 US cups. Four US cups is a close enough approximation for cooking (within 5%).
What does m³ mean in volume?
A cubic meter (m³) is 1,000 liters — the volume of a cube measuring 1 m on each side. It is used for large-scale volumes like water tanks, swimming pools, and shipping containers.