One U.S. customary cup is approximately 236.6 milliliters, usually rounded to 237 mL. A metric cup is 250 mL. For U.S. nutrition labeling, a cup means 240 mL. Choose the definition used by your recipe before converting: those three numbers describe different conventions, not three equally precise answers to the same measurement.
If a recipe already gives milliliters, the simplest approach is to measure that amount directly. If it gives cups only, the charts below convert in both directions and keep the cup sizes separate.
Which cup does your recipe mean?
The NIST conversion table lists a U.S. cup as approximately 236.5882 mL. That is the customary cup used in the first column of these charts. You do not need to measure kitchen liquids to four decimal places; the extra digits keep the arithmetic consistent before rounding.
The FDA defines a cup as 240 mL for nutrition labeling. Some recipe publishers also use 240 mL as their stated kitchen convention. Follow the publisher’s conversion notes rather than assuming every American recipe uses exactly the same rounding.
A recipe that defines its cup as 250 mL uses a metric cup. Check the recipe introduction, measurement guide, or markings on the measuring set. Country alone is not always enough to settle the question, especially for a recipe copied between websites. A drinking mug and a coffee maker’s advertised “cup” are not reliable substitutes for a defined recipe cup.
Cups to milliliters chart
U.S. customary values below are rounded to one decimal place. The 240 mL and 250 mL columns show their own definitions; do not mix columns within a recipe.
| Cups | U.S. customary (mL) | 240 mL cup (mL) | 250 mL metric cup (mL) |
|---|---|---|---|
| ¼ | 59.1 | 60.0 | 62.5 |
| ⅓ | 78.9 | 80.0 | 83.3 |
| ½ | 118.3 | 120.0 | 125.0 |
| ⅔ | 157.7 | 160.0 | 166.7 |
| ¾ | 177.4 | 180.0 | 187.5 |
| 1 | 236.6 | 240.0 | 250.0 |
| 1½ | 354.9 | 360.0 | 375.0 |
| 2 | 473.2 | 480.0 | 500.0 |
| 3 | 709.8 | 720.0 | 750.0 |
| 4 | 946.4 | 960.0 | 1000.0 |
For example, half a U.S. customary cup is about 118.3 mL. Half of a 240 mL cup is 120 mL, while half a metric cup is 125 mL. If a recipe explicitly says “½ cup (125 mL),” that printed milliliter quantity tells you which amount to use.
Milliliters to cups chart
These cup amounts are rounded to three decimal places for comparison. Decimal cups are useful for checking a conversion, but a measuring jug’s mL scale is usually easier to use than trying to estimate 0.845 cup.
| Milliliters | U.S. customary cups | 240 mL cups | 250 mL metric cups |
|---|---|---|---|
| 50 | 0.211 | 0.208 | 0.200 |
| 100 | 0.423 | 0.417 | 0.400 |
| 125 | 0.528 | 0.521 | 0.500 |
| 150 | 0.634 | 0.625 | 0.600 |
| 200 | 0.845 | 0.833 | 0.800 |
| 240 | 1.014 | 1.000 | 0.960 |
| 250 | 1.057 | 1.042 | 1.000 |
| 300 | 1.268 | 1.250 | 1.200 |
| 500 | 2.113 | 2.083 | 2.000 |
| 750 | 3.170 | 3.125 | 3.000 |
| 1000 | 4.227 | 4.167 | 4.000 |
How to convert any amount
Cups to mL: multiply the number of cups by the milliliters in your chosen cup. mL to cups: divide the number of milliliters by that same number. Use 236.5882365 for U.S. customary calculations, 240 for a stated 240 mL convention, or 250 for metric cups.
Suppose a U.S. customary recipe calls for 1½ cups of milk. Multiplying 1.5 by 236.5882365 gives about 354.9 mL, so approximately 355 mL is a practical kitchen reading. If the recipe instead specifies a 250 mL cup, the same 1½ cups is 375 mL.
For the reverse direction, 500 mL divided by 250 is exactly 2 metric cups. Dividing 500 by 236.5882365 gives about 2.113 U.S. customary cups. If you have an mL-marked jug, filling to 500 mL avoids estimating that extra fraction.
Does the difference matter in cooking?
One 250 mL cup holds about 13.4 mL more than one U.S. customary cup, a difference of roughly 5.7%. Across four cups, that becomes about 53.6 mL. A flexible soup may tolerate a little extra liquid, but a batter, dough, or concentrated sauce can be more sensitive to changed proportions.
When doubling a recipe, multiply its original quantities first and round only the final result. Four U.S. customary cups are about 946.4 mL, not a full liter. Four metric cups are exactly 1,000 mL. Switching between those amounts midway through scaling changes the recipe.
Measure the liquid, not the picture on the jug
Set a liquid measuring cup on a flat surface and check the level at eye height. The King Arthur Baking recipe success guide recommends an eye-level reading for accuracy. Holding the cup in your hand or looking steeply down at the scale can make the liquid appear to reach a different mark.
Use a vessel with divisions fine enough for the amount you need. A large jug with widely spaced marks is awkward for a small splash of vanilla or a modest oil quantity. Let foam settle before reading a liquid level. For thick liquids, allow time for the ingredient to settle and scrape out what the recipe expects you to add.
For help choosing the shape of the tool, see our guide to dry and liquid measuring cups.
Do water, milk, and flour use different mL-to-cup conversions?
The volume conversion stays the same for every ingredient when the cup definition stays the same. A 250 mL volume is one metric cup whether it contains water, milk, oil, or flour. However, those ingredients do not all weigh the same, and packing a dry ingredient changes how much material fits inside the cup.
Grams measure mass, while milliliters and cups measure volume. Do not turn a request for 200 grams into 200 mL unless an appropriate ingredient-specific conversion supports it. When a baking recipe supplies grams for flour, use a scale rather than this volume chart.
A simple rule to keep
Read the recipe’s unit notes, choose one cup definition, and stay with it. For an unspecified U.S. customary conversion, remember approximately 237 mL per cup. Use 240 mL when that convention is specified and 250 mL for a stated metric cup.
If your current jug lacks readable mL markings, you can browse liquid measuring cups with milliliter markings. Check the scale, capacity, and care instructions before choosing one.
Leave a Reply