How Many Grams in a Cup of Milk? 244, and Why It Is Not 240

Published October 19, 2026

One US cup of whole milk weighs 244 grams, according to USDA FoodData Central. If you are converting a recipe and wondering how many grams in a cup of milk, that is the number. The interesting part is the 4 extra grams. A cup of water weighs 240 grams, and milk is not water. It is water plus fat, protein, and lactose, which makes it about 3% denser than water. Four grams sounds like nothing until it is the difference between a custard that sets and one that weeps.

Why milk weighs more than water

Density does the work. Water is 1 gram per milliliter by definition. Whole milk runs about 1.03 grams per milliliter at room temperature, because the milk solids dissolved in it are heavier than the water they displace. Multiply by a US cup and you land at 244 grams. This is also why the "just use 240" shortcut most charts offer is fine for pancakes and slightly off for anything where hydration ratios matter, like bread dough or pastry cream.

Temperature nudges the number too. Cold milk straight from the fridge is marginally denser than room-temperature milk, so it weighs a gram or two more per cup. Two grams will not ruin a cake, but the point stands: the scale does not care about temperature.

The skim milk paradox

Here is the part that surprises people. Skim milk weighs slightly more per cup than whole milk, about 245 to 246 grams. The intuition says removing fat should lighten it. The physics says the opposite, because fat is less dense than water. Cream floats on raw milk for exactly this reason. Take the light stuff out and what remains is the heavier water and minerals.

In practice, the 1 to 2 gram gap between whole and skim is irrelevant in every recipe I can think of. It matters as a concept, though, because it breaks the lazy assumption that "richer equals heavier." With dairy, richer often means lighter per cup. Buttermilk, half and half, and heavy cream all follow the same logic in their own ranges.

The conversion table

If you are converting a European recipe, that last row is the one to watch. A metric cup is 250 milliliters, not 236.6, so it holds about 257 grams of milk. Using the US 244-gram figure on a metric recipe under-measures every cup by 13 grams. Over 4 cups of milk in a bread dough, that is 52 grams of missing hydration, which you will feel in the crumb.

What about non-dairy milk

Almond, oat, and soy milks are mostly water with a small fraction of plant solids, so they land very close to water's density: roughly 240 to 243 grams per US cup. The honest answer is that published figures vary by brand, because the solids content varies by brand. For baking with non-dairy milk, 240 grams per cup is a safe working number, and the recipe will not know the difference.

One exception to file away: canned coconut milk is much richer, around 240 grams per cup as well but with far more fat. The weight tells you how much to add, not how that fat will behave once it is in the recipe.

When the grams actually matter

For most everyday cooking, they do not. A splash more or less milk in scrambled eggs, oatmeal, or a smoothie changes nothing. The grams start to matter in three places: custards and pastry creams, where the liquid-to-egg ratio sets the texture; bread doughs, where hydration percentage is the whole recipe; and scaled-up batches, where a 4-gram-per-cup error multiplies across 20 cups into an 80-gram mistake.

For liquids, put the bowl on the scale, hit tare, and pour to the gram weight. It is faster than filling a liquid measuring cup to the line, and you skip the meniscus reading, the spilled dribble down the side, and the second trip to the sink. The liquids vs dry ingredients guide covers which measuring tools to trust for what, and the weighing vs measuring piece has the accuracy numbers if you want convincing.

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