Convert Ounces (fl oz) to Milliliters (mL)

What Is a Fluid Ounce?

The US fluid ounce (fl oz) is a customary unit of volume equal to 2 tablespoons, 6 teaspoons, or approximately 29.5735 milliliters. It is the primary unit for beverage sizes, recipe measurements, and nutrition labels in the United States.

What Is a Milliliter?

The milliliter (mL) is a metric unit of volume equal to one thousandth of a liter (0.001 L) or 1 cubic centimeter (cm³). It is the international standard for precise liquid measurement in medicine, science, cosmetics, and cooking.

Fluid Ounces to Milliliters Formula

The conversion factor is:

milliliters = fluid ounces × 29.5735

Derived from: 1 US fl oz is defined as 1/128 of a US gallon = 29.5735295625 mL.

Worked Example

Convert 8 fluid ounces (1 US cup) to milliliters:

1. Multiply: 8 × 29.5735 = 236.6 mL

So 8 fl oz = about 237 mL — one US cup. This is why "240 mL ≈ 1 cup" is a common kitchen approximation.

Quick Estimation

1 fl oz ≈ 30 mL — just multiply by 30. This undershoots by only 1.4%. Example: 12 fl oz (a soda can) × 30 = 360 mL (exact: 355 mL). Good enough for everyday estimates, but use 29.57 for precision.

Common Fluid Ounces to Milliliters Conversions

Which Is Bigger: Fluid Ounce or Milliliter?

A US fluid ounce is about 30 times larger than a milliliter. One fl oz ≈ 29.57 mL. Think of it this way: a fluid ounce is about 2 tablespoons, while a milliliter is about ¼ of a teaspoon.

When You Need This Conversion

• Adapting US recipes for metric kitchens: A recipe calling for 6 fl oz of cream = about 177 mL. Many digital kitchen scales support mL for liquid ingredients.
• Cocktail recipes: US cocktail recipes use fl oz. A classic Margarita calls for 2 fl oz (60 mL) tequila, 1 fl oz (30 mL) lime juice, 1 fl oz (30 mL) Cointreau.
• Product comparison: US products are labeled in fl oz; international products in mL. A US 16 fl oz shampoo = 473 mL, comparable to a 500 mL international bottle.