If you’ve ever tried following a recipe from a different country, you’ve probably wondered: exactly how many ml are in a cup? The answer isn’t as straightforward as you’d expect, because cup sizes vary by region. This guide breaks down the different standards so you never have to guess again.
US customary cup: 236.6 ml ·
UK metric cup: 250 ml ·
US legal cup: 240 ml ·
1/4 US cup: 59.1 ml ·
1/2 US cup: 118.3 ml
Quick snapshot
- Equals 236.6 ml (Wikipedia – Cup (unit))
- Used in US recipes (Wikipedia – Cup (unit))
- Based on US pint (Wikipedia – Cup (unit))
- Equals 250 ml (Wikipedia – Cup (unit))
- Used in most Commonwealth countries (Wikipedia – Cup (unit))
- Standard in international recipes (Wikipedia – Cup (unit))
- Equals 250 ml (Wikipedia – Cup (unit))
- Same as metric cup (Wikipedia – Cup (unit))
- Used in the UK (Wikipedia – Cup (unit))
- Equals 240 ml (Wikipedia – Cup (unit))
- Used for nutrition labeling (Wikipedia – Cup (unit))
- Based on FDA regulations (Wikipedia – Cup (unit))
Five major cup standards, one consistent pattern: the volume varies by up to 50 ml depending on which system a recipe follows.
| Label | Value | Source |
|---|---|---|
| US cup (customary) | 236.6 ml | Wikipedia – Cup (unit) |
| UK cup (metric) | 250 ml | Wikipedia – Cup (unit) |
| US legal cup | 240 ml | Wikipedia – Cup (unit) |
| Japanese cup | 200 ml | Wikipedia – Cup (unit) |
| Australian cup | 250 ml | Wikipedia – Cup (unit) |
What is 1 cup in mL in the UK?
UK cup measurement definition
- The modern UK standard for a cup is 250 ml, identical to the metric cup (Wikipedia – Cup (unit) defines the metric cup as 250 ml).
- British recipes generally avoid cup measurements and prefer grams and millilitres (Delicious Magazine – US to UK cups to grams conversion guide).
Comparison with US cup
- A US customary cup is 236.6 ml, so a UK cup is 13.4 ml larger (Wikipedia – Cup (unit) lists US customary cup as 236.6 ml).
- The US legal cup used for nutrition labels is 240 ml, still 10 ml less than the UK metric cup (Wikipedia – US legal cup defined as 240 ml).
The implication: if you use a US measuring cup for a UK recipe, you’ll be slightly short.
Is 1 cup 200 or 250ml?
Standard US cup size
- The US standard cup is 236.6 ml, often rounded to 237 ml in cooking charts (OpenTextBC – Imperial and U.S. Systems of Measurement).
Metric cup size
- The metric cup is exactly 250 ml, used in Australia, New Zealand, and many international recipes (Wikipedia – Cup (unit) defines metric cup as 250 ml).
Why 200ml is sometimes used
- Japan uses a 200 ml cup (Wikipedia – Cup (unit) lists Japanese cup as 200 ml).
- Some older or regional recipes may reference a 200 ml cup, but it’s not a mainstream standard elsewhere.
The catch: assuming 1 cup equals 200 ml will leave you short in any standard recipe outside Japan.
Is 250ml the same as 1 cup?
Conversion equivalence
- In metric countries, yes: 250 ml equals exactly 1 metric cup (Wikipedia – Cup (unit)).
- In the US customary system, 250 ml is about 1.06 cups (236.6 ml per cup) (Weekend Bakery – Baking Conversion Table).
Why 250ml is not always 1 cup
- Because the US customary cup is smaller, pouring 250 ml into a US measuring cup will overflow by 13.4 ml.
- For nutrition labeling in the US, a cup is 240 ml, so 250 ml is 1.04 US legal cups (Wikipedia – US legal cup defined as 240 ml).
Why this matters: if you’re following a US recipe with a metric measuring cup, you’ll add roughly an extra tablespoon of liquid per cup.
Is 250ml a full cup?
Full cup definition
- In the metric system, 250 ml is exactly one full cup.
- In the US customary system, 250 ml is slightly more than one cup (236.6 ml).
Volume of 250 ml
- 250 ml equals 8.45 US fluid ounces, whereas one US cup is 8 fl oz (WebstaurantStore – Cooking Measurement Conversion Chart).
- So 250 ml fills a US cup and leaves about half a tablespoon extra.
The trade-off: recipes that call for “1 cup” without specifying the standard can lead to under- or over-measurement depending on your location.
Is 2 cups the same as 500ml?
500 ml to cups
- 2 metric cups = 500 ml exactly (Wikipedia – Cup (unit)).
- 2 US customary cups = 473.2 ml (Wikipedia – Cup (unit) gives 236.6 ml per US cup).
- 2 US legal cups = 480 ml (Wikipedia – US legal cup defined as 240 ml).
2 cups to ml
- For a US recipe, 2 cups is 473 ml. For a metric recipe, it’s 500 ml. The difference is about 27 ml, roughly 2 tablespoons.
The pattern: the gap between US and metric cups doubles as you scale up, so converting larger quantities without knowing the standard can noticeably alter a recipe’s outcome.
Two cup standards, one clear gap: the difference between 2 US cups and 2 metric cups is 27 ml, enough to affect texture in baking.
| Cup Type | Volume (ml) | Notes |
|---|---|---|
| US Customary | 236.6 | Standard for home recipes in the US |
| US Legal | 240 | Used on nutrition labels in the US |
| Metric | 250 | Used in Australia, NZ, most Commonwealth countries |
| UK | 250 | Same as metric cup; UK recipes often use weight instead |
| Japanese | 200 | Used in Japanese home cooking |
| Canadian | 250 | Canada adopted metric cup |
Detailed conversion table for common fractional cup amounts.
| Cups | US Customary (ml) | Metric (ml) |
|---|---|---|
| 1/8 | 29.6 | 31.3 |
| 1/4 | 59.1 | 62.5 |
| 1/3 | 78.9 | 83.3 |
| 1/2 | 118.3 | 125.0 |
| 2/3 | 157.7 | 166.7 |
| 3/4 | 177.4 | 187.5 |
| 1 | 236.6 | 250.0 |
| 1.5 | 354.9 | 375.0 |
| 2 | 473.2 | 500.0 |
| 3 | 709.8 | 750.0 |
| 4 | 946.4 | 1000.0 |
How to Convert Cups to ml: Step by Step
- Identify the cup standard used in your recipe. Check the origin or any notes (US, metric, UK, legal).
- Look up the ml equivalent using the tables above. For a US recipe, use 236.6 ml per cup; for metric, use 250 ml.
- Multiply the number of cups by the equivalent. For example, 2.5 US cups × 236.6 = 591.5 ml.
- Use a liquid measuring cup with ml markings for accuracy. For dry ingredients, consider weight (grams) instead, as density varies.
Home bakers who mix recipes from the US and metric sources face a systematic error of up to 5% in liquid ingredients. Using the right standard can save a cake from a dry or soggy fate.
Confirmed facts
- US customary cup = 236.6 ml (Wikipedia – Cup (unit))
- UK metric cup = 250 ml (Wikipedia – Cup (unit))
- US legal cup = 240 ml for nutrition (Wikipedia – Cup (unit))
What’s unclear
- Historical variations in cup sizes across countries (e.g., some older UK references to a 225 ml or 284 ml cup) (Dylan Leigh – Cooking cup measurements discussion)
- Exact legal definitions may vary by jurisdiction (e.g., Canada uses metric but some older cookbooks reference imperial cups).
Expert Perspectives
“The metric cup is 250 ml and is commonly used in Australia, New Zealand, and other metric-based countries.”
— Wikipedia article on cup (unit)
“A US customary cup is 236.588 millilitres, commonly rounded to 237 mL in cooking charts.”
— Exploratorium.edu – measurement equivalents
For bakers adjusting international recipes, the choice is clear: identify the cup standard first, then use the correct ml equivalent, or switch to weight measurements to eliminate volume ambiguity. How to Bake a Cheesecake often requires precision. For other conversions, see 145 Pounds in kg.
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Frequently asked questions
How many ml in 3/4 cup?
In US customary: 177.4 ml. In metric: 187.5 ml (Weekend Bakery – Baking Conversion Table).
How many ml in 2/3 cup?
In US customary: 157.7 ml. In metric: 166.7 ml.
Is 1 cup 250 ml in Canada?
Yes, Canada uses the metric cup of 250 ml (Wikipedia – Cup (unit) notes Canada uses metric cup).
How do I convert cups to ml for baking?
Multiply the number of cups by the standard value: 236.6 ml for US, 250 ml for metric. For best accuracy, use a scale and convert to grams (Delicious Magazine conversion guide).
What is the difference between a US cup and a UK cup?
The US customary cup is 236.6 ml; the UK metric cup is 250 ml. The UK rarely uses cup measures in modern recipes (Delicious Magazine).
How many ml in a cup of medicine?
Medicine dosing cups often use 240 ml (US legal) or 250 ml (metric). Always check the label (Wikipedia – Cup (unit)).
How many ml in a coffee cup?
A standard coffee cup is about 237–240 ml, but coffee makers often use the 150 ml “cup” for brewing (Shamrock Foods conversion chart).