Fluid Ounces to Milliliters (fl oz to mL) Converter
Use this fluid ounces to milliliters converter to instantly convert fl oz to mL with accurate results. Enter a volume in fluid ounces, adjust decimal precision, and get the equivalent milliliters value immediately.
This converter uses the exact formula mL = fl oz × 29.5735 for US fluid ounces. One fluid ounce is 29.5735 mL — a conversion you'll use constantly in cooking, bartending, medicine, and any situation where American volume labels meet metric measuring tools.
Formula used: mL = fl oz × 29.5735
Need to convert milliliters to fluid ounces? Try our Milliliters to Fluid Ounces Converter.
Fluid Ounces to Milliliters Formula
To convert fluid ounces to milliliters, multiply by 29.5735.
Formula: mL = fl oz × 29.5735
For example, 12 fl oz × 29.5735 = 354.88 mL (a standard US soda can).
One US fluid ounce is defined as exactly 29.5735295625 milliliters. This is derived from the gallon: 1 US gallon = 231 cubic inches = 3785.411784 mL, and 1 gallon = 128 fluid ounces, so 1 fl oz = 3785.411784 ÷ 128 = 29.5735... mL. The definition is exact — all decimal places in the conversion factor are significant.
Why 29.5735? The History of the Fluid Ounce
The fluid ounce emerged from the British apothecary system as a volume approximately equal to the volume of a troy ounce of water. The US customary fluid ounce was historically defined as the volume of an avoirdupois ounce of distilled water at 62°F, which settled at approximately 29.57 mL. The modern definition ties the fluid ounce precisely to the gallon and the liter. The US fluid ounce (29.57 mL) is slightly different from the UK fluid ounce (28.41 mL) — a historical divergence that causes real confusion on beverage labels and recipe books that travel between the two countries.
Common Sizes: Fluid Ounces to Milliliters
- 1 fl oz = 29.57 mL — approximately 1 shot of spirits
- 8 fl oz = 236.59 mL — 1 US cup of liquid
- 12 fl oz = 354.88 mL — standard US soda or beer can
- 16 fl oz = 473.18 mL — 1 US pint (a standard large coffee)
- 32 fl oz = 946.35 mL — 1 US quart (just under 1 liter)
Fluid Ounces to Milliliters Conversion Table
| Fluid Ounces (fl oz) | Milliliters (mL) |
|---|---|
| 1 fl oz | 29.57 mL |
| 2 fl oz | 59.15 mL |
| 4 fl oz | 118.29 mL |
| 6 fl oz | 177.44 mL |
| 8 fl oz | 236.59 mL |
| 12 fl oz | 354.88 mL |
| 16 fl oz | 473.18 mL |
| 20 fl oz | 591.47 mL |
| 32 fl oz | 946.35 mL |
| 64 fl oz | 1892.71 mL |
When to Convert Fluid Ounces to Milliliters
Cooking and baking with metric tools: Many modern kitchens have metric measuring cups and graduated cylinders that show mL but not fl oz. When following a US recipe that calls for 6 fluid ounces of cream, knowing that's 177.44 mL lets you measure accurately with a metric jug. This is one of the most common reasons home cooks look up fluid ounce conversions.
Medicine and pharmaceuticals: US prescriptions and over-the-counter dosing instructions are sometimes expressed in fluid ounces (especially for liquid medications and children's doses). Medical professionals and pharmacists working with metric dispensing equipment convert fl oz to mL to ensure precise dosing. The 30 mL approximation (1 fl oz ≈ 30 mL) is commonly used in medical contexts for simplicity, though the exact value of 29.5735 mL matters for concentrated medications.
Cocktails and bartending: Cocktail recipes from American sources use fluid ounces, while bartenders in metric countries work in milliliters. A standard 1.5 fl oz shot is 44.36 mL — often rounded to 44 or 45 mL in metric bar guides. A 2 fl oz pour is 59.15 mL. Converting these amounts ensures consistent drink strength across different bar setups.
Cosmetics and personal care: US cosmetic products are labeled in fl oz on front-facing packaging (as required by US law) with mL in smaller print. When purchasing cosmetics abroad, or when comparing a 3.4 fl oz travel-size product to its 100 mL equivalent, the conversion confirms they are the same size (3.4 fl oz = 100.55 mL — the exact size allowed in carry-on liquids at airports).
TSA liquid rules and travel: The US Transportation Security Administration's 3-1-1 rule limits carry-on liquids to containers of 3.4 fl oz or less. This equals 100.55 mL. Understanding this conversion prevents the frustration of having to discard liquids at security — a 100 mL bottle passes; a 101 mL bottle technically does not.
FAQ
How many mL is 1 fluid ounce?
1 US fl oz = exactly 29.5735 mL. In medicine this is commonly rounded to 30 mL for ease of calculation, but the precise value is 29.5735295625 mL.
How many mL is 8 fl oz (1 cup)?
8 fl oz = approximately 236.588 mL. This is the standard US cup measurement — sometimes rounded to 240 mL on nutrition labels (the "US legal cup").
How many mL is a 12 fl oz soda can?
12 fl oz = 354.88 mL. The standard US 12-ounce can holds about 355 mL, which is why international can sizes are often labeled as 355 mL rather than 360 or 350 mL.
Is 1 fl oz = 30 mL exactly?
No — 1 US fl oz = 29.5735 mL. The 30 mL approximation is used in medicine for simplicity (and because most medical syringes are graduated in 1 mL increments, making 29.57 impractical). For precise measurements in cooking or science, use the full value.
What is the difference between US and UK fluid ounces?
A US fluid ounce = 29.5735 mL. A UK fluid ounce = 28.4131 mL. They differ by about 4%. When reading recipes or label volumes from British sources, double-check which fluid ounce is being used — this converter uses the US fl oz.