Cups to mL Converter
Result
236.588 mL
Quick Reference
How Cups to mL Conversion Works
A cup-to-milliliter conversion translates a volume measurement from the cup unit (used primarily in US, Australian, and older British recipes) into the metric milliliter unit used worldwide. The National Institute of Standards and Technology (NIST) defines one US customary cup as exactly 236.5882365 milliliters, derived from the legal definition of 1 US gallon = 3,785.411784 mL divided by 16.
This conversion is essential for anyone following international recipes, scaling formulas in food manufacturing, or measuring liquid medications. According to a 2023 survey by the International Bureau of Weights and Measures (BIPM), over 95% of the world's countries use the metric system as their official standard of measurement, making milliliters the dominant volume unit globally. The United States, Liberia, and Myanmar remain the only countries that have not officially adopted the metric system for everyday use.
Cooks, bakers, bartenders, and pharmacists frequently need this conversion. A barista making pour-over coffee with a 15:1 water-to-coffee ratio needs precise mL measurements. Home cooks adapting American recipes for European kitchens need reliable conversions. Use our Cooking Converter for multi-unit cooking conversions and the Volume Converter for general volume unit conversion.
The Cups to mL Formula
The formula for converting cups to milliliters is defined by NIST unit standards:
Milliliters = Cups x Conversion Factor
- US Cup conversion factor: 236.588 mL per cup
- Metric Cup conversion factor: 250 mL per cup (exact)
- Imperial Cup conversion factor: 284.131 mL per cup
Worked example: A recipe calls for 2.5 US cups of chicken broth. Converting: 2.5 x 236.588 = 591.47 mL. On a metric measuring jug, you would fill to just under the 600 mL mark. The difference from 600 mL is only 8.53 mL (about half a tablespoon), which is negligible for broth but could matter in precision baking.
Key Terms You Should Know
- US Customary Cup -- The standard cup used in American recipes, equal to 236.588 mL, 8 US fluid ounces, or 16 US tablespoons. This is the default when a US recipe simply says "cup" without further qualification.
- Metric Cup -- Used in Australia, New Zealand, and Canada, equal to exactly 250 mL. It was adopted during metrication to provide a round-number alternative to the US cup.
- Imperial Cup -- The British Imperial cup equals 284.131 mL (10 Imperial fluid ounces). Rarely used in modern recipes but still appears in older British cookbooks published before the 1970s.
- Milliliter (mL) -- A metric unit of volume equal to one-thousandth of a liter (0.001 L). One mL equals exactly 1 cubic centimeter (cm3). Milliliters are the standard for liquid measurement in science, medicine, and international cooking.
- Fluid Ounce vs. Milliliter -- One US fluid ounce equals 29.5735 mL. Since 1 cup = 8 fl oz, this gives 8 x 29.5735 = 236.588 mL. UK fluid ounces are slightly smaller at 28.4131 mL each.
Cups to mL Conversion Table
This reference table shows common cup-to-milliliter conversions for all three cup standards. Values are based on the conversion factors defined by NIST Handbook 44.
| Cups | US Cup (mL) | Metric Cup (mL) | Imperial Cup (mL) |
|---|---|---|---|
| 1/4 cup | 59.1 | 62.5 | 71.0 |
| 1/3 cup | 78.9 | 83.3 | 94.7 |
| 1/2 cup | 118.3 | 125.0 | 142.1 |
| 2/3 cup | 157.7 | 166.7 | 189.4 |
| 3/4 cup | 177.4 | 187.5 | 213.1 |
| 1 cup | 236.6 | 250.0 | 284.1 |
| 1.5 cups | 354.9 | 375.0 | 426.2 |
| 2 cups | 473.2 | 500.0 | 568.3 |
| 3 cups | 709.8 | 750.0 | 852.4 |
| 4 cups | 946.4 | 1,000.0 | 1,136.5 |
Practical Examples
Baking a cake from a US recipe in Europe: A recipe calls for 1-3/4 cups of all-purpose flour. Converting: 1.75 x 236.588 = 414.0 mL. On your metric measuring cup, fill to just above the 400 mL line. For greater accuracy, weigh the flour instead -- 1.75 US cups of spooned-and-leveled flour equals approximately 210 grams. Use our Oz to Grams Converter for weight conversions.
Converting an Australian recipe for the US kitchen: An Australian recipe calls for 2 cups of milk. Since Australian cups are 250 mL, that is 500 mL total. Using US cups: 500 / 236.588 = 2.11 US cups. You need about 2 US cups plus 2 tablespoons (roughly 26 mL) to match the recipe's intended volume.
Measuring cocktail ingredients: A punch recipe calls for 3/4 cup of lime juice. Converting: 0.75 x 236.588 = 177.4 mL. If your bar jigger measures in ounces, that is 6 fluid ounces. This precision matters in cocktails where the acid-to-sugar balance is critical to flavor.
Tips for Accurate Cups to mL Conversion
- Identify the cup standard first: Before converting, determine whether your recipe uses US cups (236.6 mL), metric cups (250 mL), or Imperial cups (284.1 mL). Australian and New Zealand recipes use metric cups. Most American cookbooks and websites use US cups.
- Use a graduated metric measuring cup: If you frequently convert between cups and mL, invest in a measuring cup that shows both scales. Pyrex and OXO both make cups with dual US and metric markings.
- Round sensibly for cooking: For soups, stews, and sauces, rounding 236.6 mL to 240 mL (a difference of 1.4%) is perfectly acceptable. For baking, stick to the precise value or convert to weight.
- Remember the quick approximation: 1 US cup is roughly 240 mL. This approximation is within 1.4% of the true value and is easy to calculate mentally. Four cups is about 960 mL, close enough to 1 liter for casual cooking.
- Double-check fractional conversions: Common fractions like 1/3 cup (78.9 mL) and 2/3 cup (157.7 mL) are harder to eyeball on a metric measuring cup. Write these values down or bookmark this page for quick reference.
History of the Cup as a Measurement Unit
The standardized measuring cup was popularized in 1896 by Fannie Farmer in the Boston Cooking-School Cook Book, which was the first major cookbook to insist on level, standardized measurements rather than the imprecise "handfuls" and "heaps" common in earlier recipes. The US cup was legally defined as half a US liquid pint (8 US fluid ounces) and standardized at 236.588 mL when NIST formalized US customary-to-metric conversions. The metric cup (250 mL) was introduced in Australia in 1970 during its metrication process and has since been adopted in New Zealand and Canada. Today, professional culinary schools worldwide teach metric measurements, though home cooking in the US remains predominantly cup-based.
Frequently Asked Questions
How many mL are in 1 cup?
One US customary cup equals exactly 236.588 milliliters. This value is defined by the National Institute of Standards and Technology (NIST). However, cup sizes vary by country: an Australian metric cup is 250 mL, a Canadian metric cup is also 250 mL, and a UK Imperial cup is 284.131 mL. When converting cups to mL, always verify which cup standard your recipe uses. For US recipes, multiply the number of cups by 236.588 to get the equivalent in milliliters.
What is the difference between a US cup and a metric cup?
A US customary cup equals 236.588 mL, while a metric cup (used in Australia, New Zealand, and Canada) equals exactly 250 mL. The metric cup is 5.7% larger than the US cup. This means a recipe calling for 2 metric cups of flour requires 500 mL, but 2 US cups only equals 473.2 mL -- a 26.8 mL difference. In baking, this 5.7% discrepancy can noticeably affect texture and rise. Always check whether a recipe uses US or metric measurements before converting.
How do I convert 2/3 cup to mL?
Two-thirds of a US cup equals approximately 157.7 mL. The calculation is straightforward: multiply 2/3 (0.6667) by 236.588 mL per cup, which gives 157.725 mL. For practical cooking, you can round to 158 mL or use the 150 mL mark on a metric measuring cup plus about half a tablespoon (7.5 mL) extra. If using a metric cup (250 mL), two-thirds equals 166.7 mL. Our converter handles fractional cups automatically -- just enter 0.667 in the input field.
Why do different countries use different cup sizes?
Different cup sizes exist because the US retained its customary measurement system while most countries adopted the metric system at different times. The US cup (236.588 mL) descends from British colonial measures. When Australia metricated in 1970, it rounded to 250 mL for simplicity. The UK Imperial cup (284.131 mL) comes from the 1824 British Weights and Measures Act but is now rarely used, with most modern UK recipes using milliliters directly. Japan uses a 200 mL cup for rice measurement, adding yet another variant.
How many mL is half a cup?
Half a US cup equals approximately 118.3 mL (precisely 118.294 mL). This is calculated by dividing 236.588 mL by 2. For practical cooking, 120 mL is a close enough approximation -- the 1.4% difference will not noticeably affect most recipes. If you are working with a metric cup (250 mL), half equals exactly 125 mL. Half an Imperial cup equals 142.1 mL. Knowing these half-cup values is particularly useful for baking, where recipes frequently call for 1/2 cup of ingredients like sugar, butter, or milk.
Is 250 mL the same as 1 cup?
It depends on which cup you mean. A metric cup (used in Australia, New Zealand, and Canada) is exactly 250 mL, so yes. However, a US cup is only 236.588 mL -- about 13.4 mL less than 250 mL. If a US recipe calls for 1 cup and you measure 250 mL, you will have 5.7% more than intended. For cooking soups or sauces, this difference is negligible. For baking, especially pastry and bread, the extra volume can affect the liquid-to-flour ratio and change the final texture.