Fluid ounces (fl oz)

The US fluid ounce is a unit of volume equal to 1/128 of a US gallon, about 29.57 mL.

Convert fluid ounces to any volume unit

1 fluid ounce = 0.02957352956 liters

Quick facts

Unit
Fluid ounce (plural: fluid ounces)
Symbol
fl oz
Measures
Volume / Capacity
System
US liquid
Equals
0.029573529563 liters
Definition
1/128 of a US gallon (about 29.5735 mL).
Also written
US fluid ounce, oz (liquid), floz

1 fluid ounce in other units

Liters0.02957352956 L
Gallons0.0078125 gal
Milliliters29.57352956 mL
Cups0.125 cup
Tablespoons2 tbsp
Teaspoons6 tsp
Cubic meters0.00002957353 m³
Pints0.0625 pt

What is a fluid ounce?

The US fluid ounce is a unit of volume equal to 1/128 of a US gallon, about 29.57 mL. It is used on drink labels, in recipes and for medicine in the United States.

A fluid ounce measures volume, while an ounce measures weight; a fluid ounce of water happens to weigh about 1.04 ounces. The imperial fluid ounce used in the UK is slightly smaller, 28.41 mL.

Where the fluid ounce sits among volume units

The fluid ounce is number 37 of 234 on our scale of volume units, ordered from smallest to largest.

Tablespoon1 fl oz = 2 tbsp Metric tablespoon1 fl oz = 1.97157 metric tablespoon Cubic inch1 fl oz = 1.80469 in³ Imperial fluid ounce1 fl oz = 1.04084 imp fl oz Fluid ouncethis unit Shot1 shot = 1.5 fl oz Deciliter1 dL = 3.3814 fl oz Cup1 cup = 8 fl oz Metric cup1 metric cup = 8.45351 fl oz

What fluid ounces are used for

  • Drink and beverage labels
  • Liquid medicine and baby bottles
  • Cocktail recipes
  • Cosmetics

Fluid ounces in real life

  • A US can of soda is 12 fl oz
  • A standard shot is 1.5 fl oz
  • A US cup is 8 fl oz
  • TSA carry-on liquids are limited to 3.4 fl oz (100 mL)

One fluid ounce is enough to fill about 5.9 teaspoons, or about 67% of a shot glass, or about 8.3% of a soda can, or enough to fill about 591 drops of water.

Top fluid ounce conversions

Common amounts of fluid ounces

Convert fluid ounces to all 233 other units

Metric

US liquid

US dry

Imperial (UK)

Wine & spirits

Cooking (metric & informal)

Oil, gas & shipping

Scientific

Ancient

East & Southeast Asian

European (pre-metric)

Everyday comparisons

Convert to fluid ounces

Frequently asked questions

What is a fluid ounce?

The US fluid ounce is a unit of volume equal to 1/128 of a US gallon, about 29.57 mL.

How is the fluid ounce defined?

1/128 of a US gallon (about 29.5735 mL).

How many liters are in a fluid ounce?

One fluid ounce equals 0.02957352956 liters.

How many gallons are in a fluid ounce?

One fluid ounce equals 0.0078125 gallons.

How many milliliters are in a fluid ounce?

One fluid ounce equals 29.57352956 milliliters.