About this tool
Enter US fluid ounces to get milliliters, or enter milliliters to get fluid ounces. One US fluid ounce is exactly 29.5735295625 ml, which is usually rounded to 29.57 ml (some labels round it to 30 ml). Everything runs in your browser.
How to use it
Type the number of ounces in the left box and read the milliliters on the right, or do the reverse. This tool measures volume, the amount of liquid. It is not for weight, so use the grams to ounces converter for dry goods.
How to convert oz to ml by hand
Multiply fluid ounces by 29.57. A quick shortcut is to multiply by 30 and take off a little: 8 fl oz times 30 is 240, and the exact answer is 236.6 ml. For milliliters to ounces, divide by 30 and add a little.
Fluid ounces to milliliters
| US fluid ounces | Milliliters |
|---|---|
| 1 fl oz | 29.6 ml |
| 2 fl oz | 59.1 ml |
| 4 fl oz | 118.3 ml |
| 8 fl oz | 236.6 ml |
| 12 fl oz | 354.9 ml |
| 16 fl oz | 473.2 ml |
| 20 fl oz | 591.5 ml |
| 32 fl oz | 946.4 ml |
| 64 fl oz | 1892.7 ml |
| 128 fl oz | 3785.4 ml |
Common drink sizes in ounces
| Milliliters | US fluid ounces |
|---|---|
| 100 ml | 3.38 fl oz |
| 250 ml | 8.45 fl oz |
| 330 ml | 11.16 fl oz |
| 355 ml | 12.00 fl oz |
| 500 ml | 16.91 fl oz |
| 750 ml | 25.36 fl oz |
| 1000 ml | 33.81 fl oz |
Ounces in a cup, quart, gallon and liter
A US cup is 8 fl oz (236.6 ml), a pint is 16 fl oz, a quart is 32 fl oz, and a gallon is 128 fl oz (3.785 liters). One liter is about 33.81 fl oz. These steps are useful when a recipe or bottle label uses one unit and your measuring jug uses another.
Where people need oz to ml
- Cooking and baking: recipes from the US list fluid ounces, while measuring jugs elsewhere show milliliters.
- Air travel: carry-on liquid limits are given as 100 ml (3.4 fl oz), so a 4 oz bottle is over the limit.
- Baby bottles and hydration: bottles are marked in ounces, while health guidance often uses milliliters.
- Drinks and cocktails: a standard shot is 1.5 fl oz, or about 44 ml.
Things to watch out for
There are three different "ounces". The US fluid ounce is 29.57 ml, the UK imperial fluid ounce is 28.41 ml, and the ounce used for weight is about 28.35 grams. They are not interchangeable. This page converts US fluid ounces, which is what American recipes and labels almost always use. If the recipe comes from the UK, the imperial ounce is about 4% smaller.
Frequently asked questions
1 US fluid ounce is 29.5735 ml, usually rounded to 29.57 ml. A 1 oz measure is therefore about 30 ml.
8 US fluid ounces, which is one cup, equals about 236.6 ml.
No. A fluid ounce measures volume (29.57 ml) and a weight ounce measures mass (about 28.35 g). They only match closely for water-like liquids and it is better not to assume it.