ml to oz Converter – Fluid Ounces
Convert milliliters to fluid ounces and back in one click — US customary, US nutrition-labeling or UK imperial ounces. Type a value in either field and get cups, tablespoons and teaspoons too.
Convert Milliliters to Fluid Ounces — and Fluid Ounces Back to Milliliters
ml to oz Formula
Where:
- \(V_{\text{mL}}\) — the volume in milliliters
- \(F\) — the number of milliliters in one fluid ounce, set by the ounce type you select
- US customary: \(F = 29.5735295625\) mL, because 1 fl oz is 1/128 of the 3.785 L US gallon
- US nutrition labeling: \(F = 30\) mL, the rounded value the FDA allows on food labels
- UK imperial: \(F = 28.4130625\) mL, because 1 imperial fl oz is 1/20 of the 568.26 mL imperial pint
The formula divides the milliliter volume by the size of the chosen fluid ounce. To convert in the other direction, multiply instead: \(\text{mL} = \text{fl oz} \times F\).
ml to oz – Calculation Example
Example: a travel-size bottle holds 100 mL of shampoo. You want to know its volume in US customary fluid ounces.
\[ \text{fl oz} = 100 \div 29.5735295625 = 3.3814 \]
Result: 100 mL = 3.3814 fl oz. That is about 0.423 US cups, 6.76 US tablespoons or 20.29 US teaspoons.
How to use the calculator
- Type a number in Milliliters (mL) — the converter works out the fluid ounces automatically. Or type in the Fluid ounces (fl oz) field instead and it converts back into milliliters.
- The calculator follows the field you edited last, so you can keep adjusting either side without clearing the other.
- Choose the Fluid ounce type from the dropdown: US customary for everyday recipes and drinks, US nutrition labeling for the 30 mL ounce used on FDA food labels, or UK imperial for British recipes.
- Read the results: fluid ounces, milliliters, US cups, US tablespoons and US teaspoons, plus the exact formula with your values, a table of common bottle and can sizes, and a full 1–64 fl oz conversion table.
What is a fluid ounce?
A fluid ounce (fl oz) is a unit of volume, not weight: it answers
Frequently Asked Questions
Is 1 fl oz the same as 1 oz?
No. The fluid ounce (fl oz) measures volume, while the ounce (oz) measures weight. They only nearly coincide for water: 1 mL of water weighs about 1 g, so 1 US customary fl oz of water (29.5735 mL) weighs about 1.04 oz. Honey weighs roughly 1.5 times more per the same volume, and oils weigh slightly less. For dry ingredients like flour or sugar, always measure by weight, not by fluid ounces.
Why do water bottles say 16.9 fl oz instead of a round number?
Because 500 mL — a round metric size — equals 16.907 US customary fluid ounces, which manufacturers round to 16.9 fl oz on the label. This is the classic case where the bottle is designed in metric units and the fluid ounce figure is just the conversion result. The same applies to 1-liter bottles, which display about 33.8 fl oz.
How do I convert mL to fl oz by hand without a calculator?
For a quick mental estimate with US customary ounces, divide milliliters by 30: 240 mL ≈ 8 fl oz, 100 mL ≈ 3.3 fl oz. The exact divisor is 29.5735295625, so the shortcut is off by only about 1.5% — fine for cooking, but not for labelling or precise work. To go the other way, multiply fluid ounces by 30 (or 29.57 for accuracy).
Which ounce type should I use for recipes and drinks?
Use US customary for American recipes, bar measurements and drink labels; use UK imperial for older British recipes and UK packaging; use the 30 mL nutrition-labeling ounce only when reading US food and beverage labels, where the FDA permits this rounded value. Mixing them up creates an error of up to about 5.5% between imperial and US customary ounces.
How many mL are in 8 fluid ounces (one cup)?
It depends on the ounce type: 8 US customary fl oz = 236.59 mL (1 US legal cup), 8 imperial fl oz = 227.30 mL, and 8 nutrition-labeling fl oz = 240 mL. This is why an American cup and a British cup are different volumes — a common source of failed baking conversions when recipes travel across the Atlantic.
Can I use this for the 3-1-1 liquids rule at airports?
Yes, as a quick check: the TSA limit of 3.4 fl oz corresponds to the 100 mL travel-size limit, because 100 mL ÷ 29.5735 = 3.38 fl oz. Note that the rule is set in metric — containers must hold 100 mL or less — so the 3.4 fl oz figure is a rounded conversion. Check the current rules of your airline and security authority before flying.
Does the calculator convert cups, tablespoons and teaspoons too?
Yes. Alongside fl oz it shows US cups, US tablespoons and US teaspoons, always using standard US kitchen measures (1 cup = 236.5882 mL = 16 tbsp = 48 tsp) regardless of the ounce type selected. Be aware that a UK metric tablespoon is 15 mL, slightly larger than the US tablespoon of 14.79 mL, and an Australian tablespoon is 20 mL.