ml to fl oz Converter
Convert millilitres to fluid ounces and back instantly. Choose UK (imperial) or US fluid ounces — 1 UK fl oz is 28.4131 ml and 1 US fl oz is 29.5735 ml, so every conversion is exact.
ml ↔ fl oz
UK fl oz = 28.4131 ml · US fl oz = 29.5735 ml.
1 UK fl oz = 28.4131 ml; 1 US fl oz = 29.5735 ml. Unlike pints, the UK fluid ounce is the smaller one.
Millilitres and fluid ounces
The millilitre is the metric unit; the fluid ounce is imperial — and once again there are two of them. The catch is the surprise: the UK (imperial) fluid ounce is the smaller one at 28.4131 ml, while the US fluid ounce is 29.5735 ml. That's the opposite of pints and gallons, where the UK measure is larger, so it's an easy trap. This converter defaults to the UK fl oz and lets you switch to US for American recipes.
250 ml = 8.80 UK fl oz (250 ÷ 28.4131) or 8.45 US fl oz. An American recipe cup of 8 US fl oz is about 237 ml. Going the other way, 5 UK fl oz = 142 ml.
ml to fl oz reference table
| Millilitres | UK fl oz | US fl oz |
|---|---|---|
| 50 ml | 1.76 | 1.69 |
| 100 ml | 3.52 | 3.38 |
| 150 ml | 5.28 | 5.07 |
| 237 ml | 8.34 | 8.01 |
| 250 ml | 8.80 | 8.45 |
| 500 ml | 17.60 | 16.91 |
Based on the exact factors 1 UK fl oz = 28.4130625 ml and 1 US fl oz = 29.5735296 ml.
When you'll need this
Following an American or vintage British recipe, measuring perfume or travel toiletries against the 100 ml cabin-bag limit, or scaling a cocktail. There are 20 UK fluid ounces in a UK pint — for larger volumes use the litres to pints converter, and for litres and gallons the litres to gallons converter. The all-in-one unit converter handles length, weight and temperature.
Frequently asked questions
How many ml are in a fluid ounce?
A UK (imperial) fluid ounce is 28.4131 ml, while a US fluid ounce is slightly larger at 29.5735 ml. Confusingly, the UK fl oz is the smaller one even though the UK pint and gallon are larger.
How do I convert ml to fl oz?
For UK fluid ounces, divide millilitres by 28.4131. For US fluid ounces, divide by 29.5735. For example, 250 ml is 8.80 UK fl oz or 8.45 US fl oz.
What's the difference between a UK and US fluid ounce?
The UK imperial fluid ounce is 28.4131 ml and the US fluid ounce is 29.5735 ml — about 4% larger. It's the opposite way round to pints and gallons, where the UK measure is the bigger one, so it's easy to get caught out.
How many ml is 8 fl oz?
8 UK fluid ounces is about 227 ml, while 8 US fluid ounces (a common US cup) is about 237 ml. Recipes that say '8 oz' of liquid usually mean a US cup of roughly 237 ml.
How do I convert fl oz to ml?
Multiply UK fluid ounces by 28.4131, or US fluid ounces by 29.5735. For example, 5 UK fl oz = 142 ml, while 5 US fl oz = 148 ml.