Enter a value in millilitres and read the result in fluid ounces straight away. The US and UK ounce are two different measures, so the Ounce type switch lets you pick the one you need. It is set to the US ounce by default, since that is the one you meet most often in recipes, drinks and product labels.

Millilitres turn up all the time even where the ounce rules day to day: on medicine bottles, in science, on imported food and drink, and on any water or wine bottle marked in metric. To picture those amounts in ounces, you convert. You see it on a 750 ml bottle, on perfume labelled 100 ml, or on a European recipe that lists 250 ml of milk.
The catch is that there is more than one ounce. The US fluid ounce is 29.5735 ml, while the UK (imperial) one is 28.4131 ml. The gap is about 4%, so by the time you reach a wine bottle it passes a whole ounce: 750 ml is 25.36 US ounces or 26.40 UK ounces. That is why you pick the measure with the Ounce type switch, and the result field shows the abbreviation of the one you are reading: US fl oz or UK fl oz.
We set the US ounce by default, since it is the one you meet most often. If a product or recipe comes from the United Kingdom, switch to the UK ounce.
Each of the two ounces has its own fixed factor. The US fluid ounce is exactly 29.5735295625 ml, and the UK one is exactly 28.4130625 ml. Both values are defined, so the conversion comes down to a single division.
Formula for the US ounce: ounces = millilitres ÷ 29.5735. For the UK ounce: ounces = millilitres ÷ 28.4131.
Example: you want to know how many ounces are in a 750 ml wine bottle. You substitute: 750 ÷ 29.5735 = 25.36 US ounces. The same bottle in the UK measure is 750 ÷ 28.4131 = 26.40 ounces. Both numbers are correct; they simply describe two different measures.
Watch out for one mix-up. The fluid ounce (fl oz) measures volume, while a plain ounce (oz) with no qualifier is usually a unit of weight equal to 28.35 g. This tool handles volume only. If a package lists flour in ounces, that is weight and you need a mass converter instead.
The table below converts common amounts to US fluid ounces, the converter's default setting. Values are rounded to two decimal places. The comparison with the UK ounce is in the table further down.
| Millilitres | US fluid ounces |
|---|---|
| 5 ml | 0.17 US fl oz |
| 10 ml | 0.34 US fl oz |
| 15 ml | 0.51 US fl oz |
| 20 ml | 0.68 US fl oz |
| 25 ml | 0.85 US fl oz |
| 30 ml | 1.01 US fl oz |
| 40 ml | 1.35 US fl oz |
| 50 ml | 1.69 US fl oz |
| 60 ml | 2.03 US fl oz |
| 80 ml | 2.71 US fl oz |
| 90 ml | 3.04 US fl oz |
| Millilitres | US fluid ounces |
|---|---|
| 100 ml | 3.38 US fl oz |
| 125 ml | 4.23 US fl oz |
| 150 ml | 5.07 US fl oz |
| 180 ml | 6.09 US fl oz |
| 187 ml | 6.32 US fl oz |
| 200 ml | 6.76 US fl oz |
| 240 ml | 8.12 US fl oz |
| 250 ml | 8.45 US fl oz |
| 300 ml | 10.14 US fl oz |
| 350 ml | 11.83 US fl oz |
| 355 ml | 12.00 US fl oz |
| Millilitres | US fluid ounces |
|---|---|
| 375 ml | 12.68 US fl oz |
| 400 ml | 13.53 US fl oz |
| 450 ml | 15.22 US fl oz |
| 500 ml | 16.91 US fl oz |
| 600 ml | 20.29 US fl oz |
| 700 ml | 23.67 US fl oz |
| 750 ml | 25.36 US fl oz |
| 1,000 ml | 33.81 US fl oz |
| 1,500 ml | 50.72 US fl oz |
Need the other direction? Use our <a href="/en/tools/oz-to-ml-converter">ounces to millilitres converter</a> with a full table for amounts given in ounces.
The same amount gives two different ounce figures, depending on which measure you use. The larger the volume, the wider the gap. The table below shows both results side by side so the scale of the difference is clear.
| Millilitres | US ounces | UK ounces | Difference |
|---|---|---|---|
| 25 ml | 0.85 US fl oz | 0.88 UK fl oz | 0.03 |
| 50 ml | 1.69 US fl oz | 1.76 UK fl oz | 0.07 |
| 100 ml | 3.38 US fl oz | 3.52 UK fl oz | 0.14 |
| 200 ml | 6.76 US fl oz | 7.04 UK fl oz | 0.28 |
| 250 ml | 8.45 US fl oz | 8.80 UK fl oz | 0.35 |
| 330 ml | 11.16 US fl oz | 11.61 UK fl oz | 0.46 |
| 500 ml | 16.91 US fl oz | 17.60 UK fl oz | 0.69 |
| 750 ml | 25.36 US fl oz | 26.40 UK fl oz | 1.04 |
| 1,000 ml | 33.81 US fl oz | 35.20 UK fl oz | 1.38 |
The UK ounce is smaller than the US one, so the same volume gives a larger number of ounces in it. The Ounce type switch in the converter picks which of these two columns you read.
Millilitres reach an ounce-minded reader through imported products and recipes. Each of these situations has its own quirk.
No, though it is a common rounding. The US ounce is 29.57 ml, which is 0.43 ml short of 30. The UK ounce is 28.41 ml. The 30 ml figure comes from labels and medicine, where it is rounded up for convenience.
100 ml is 3.38 US ounces or 3.52 UK ounces. The US calculation: 100 ÷ 29.5735 = 3.38 US fl oz.
No, that is a big mix-up. 100 ml is only 3.38 US ounces. Eight US ounces are 236.59 ml, more than twice as much.
750 ml is 25.36 US ounces or 26.40 UK ounces. The US calculation: 750 ÷ 29.5735 = 25.36 US fl oz.
No. 750 ml is 25.36 US ounces. Sixteen US ounces are 473.18 ml, roughly two thirds of a wine bottle.
No. Thirty-two US ounces are 946.35 ml, just under 200 ml more than a wine bottle.
The US ounce is 29.5735 ml and the UK (imperial) one is 28.4131 ml, so the UK ounce is about 4% smaller. At 100 ml the gap is 0.14 ounces, but at a litre it is already 1.38 ounces. You pick the right one with the Ounce type switch.
It depends on where the recipe comes from. US blogs and books use the US ounce, while UK sources usually use the imperial one. If the recipe uses cups, it is almost certainly a US source.
500 ml is 16.91 US ounces or 17.60 UK ounces.
No, though the values are close. 500 ml is 16.91 US ounces. A round 16 US ounces are 473.18 ml, so it falls just under 27 ml short.
30 ml is 1.01 US ounces, 50 ml is 1.69 ounces, and 250 ml is 8.45 ounces. You get each of these by dividing the millilitres by 29.5735.
No. The fluid ounce (fl oz) measures volume, while an ounce of weight is 28.35 g. This tool handles volume only. The mix-up is easy because for water the two values come out close, since water has a density of about 1 g/ml, but for oil or flour that coincidence no longer holds.
A US cup is 8 fluid ounces, which is 236.59 ml. Do not confuse it with a metric cup, which is a round 250 ml. The gap is about 13 ml per cup, and over several cups it adds up.
For the US ounce: ounces = millilitres ÷ 29.5735. For the UK ounce: ounces = millilitres ÷ 28.4131. The other way round, you multiply by the same value.
Divide the millilitres by 30. For 750 ml that gives 25 ounces, against an exact 25.36 US fl oz, so it comes out slightly low but close enough to get your bearings. Use the converter when you need precision.

If you have spotted a mistake in the tables or have an idea for improving the converter, write to us. We reply to every message.