A U.S. cup of water is about 227 grams, or about 8 ounces by weight. Fresh milk is listed at the same 227 grams per cup. For these liquids, 8 fluid ounces and 8 weight ounces are nearly the same.

Quick conversion
| Liquid, 1 U.S. cup | Approx. weight |
|---|---|
| Water | 227 grams (about 8 oz) |
| Fresh milk | 227 grams (about 8 oz) |
| 1/2 cup water or milk | about 113 grams |
| 1 tablespoon water | about 14 grams, or 15 mL |
King Arthur Baking’s ingredient weight chart lists both water and fresh milk at 227 grams (8 ounces) per cup. A U.S. cup is 236.59 mL per NIST conversion tables, and water’s density is very close to 1 gram per milliliter, which is why the weight lands near 237 grams if you use the exact milliliter figure; 227 g is the common kitchen rounding on that chart. See how to convert grams to cups, milliliters in a cup and the kitchen measurement conversion chart.
Why water is the exception
Fluid ounces measure volume; ounces on a scale measure weight. They line up closely only for water and similar liquids, such as milk or broth. A cup of flour or honey will not weigh 8 ounces. If a recipe lists grams of water or milk, you can pour 227 grams on a scale or use a 1-cup liquid measure.
Milk is only slightly heavier
Whole milk is a little denser than water, but not enough to change most recipes if you use a cup measure. If you need to be exact, weigh the milk. Skim milk is closer to water; cream is heavier. When a recipe lists cups of milk, a liquid measuring cup filled to the 1-cup line is what the author usually intended.

Frequently asked questions
How many grams are in a cup of water?
A U.S. cup of water is about 227 grams, or about 8 ounces by weight, on King Arthur Baking’s ingredient weight chart. That matches 8 fluid ounces of volume closely.
How many grams are in a cup of milk?
King Arthur lists fresh milk at the same 227 grams, or 8 ounces, per cup. In practice, whole milk is only a little denser than water, so a kitchen scale will show nearly the same number.
Is 8 fluid ounces the same as 8 ounces of water?
They are very close for water and similar liquids, but they are different kinds of ounce: one is volume, the other is weight. For flour or sugar, they are not the same.
Helpful kitchen tools
- OXO Good Grips 11-Pound Digital Kitchen Food Scale — Weighs in grams and ounces, with a tare (zero) button.
- OXO Good Grips 2-Cup and 4-Cup Glass Measuring Cup Set — A 2-cup and a 4-cup liquid cup with U.S. and metric marks.
- Kitchen Conversion Chart Magnet (AKS Magnets) — An 11-by-8.5-inch fridge magnet for volume and weight conversions.
- OXO Good Grips Stainless Steel Measuring Cups and Spoons, 8-Piece Set — Dry cups (1/4, 1/3, 1/2 and 1 cup) and spoons with etched marks.
As an Amazon Associate I earn from qualifying purchases.

Leave a Reply