Convert Cups to Grams: Water

Convert cups of water to grams with this complete reference table. 1 cup of water = 240g (USDA FoodData Central, spooned-and-leveled method). Use the table below for fractions from 1/8 cup up to 4 cups. For precision baking, weight measurements in grams are always more reliable than volume measurements in cups, because water density can vary by measuring technique.

1 cup
240g
1/2 cup
120g
2 cups
480g

Water Cups to Grams Table

CupsGrams
1/8 cup30g
1/4 cup60g
1/3 cup80g
1/2 cup120g
2/3 cup160g
3/4 cup180g
1 cup240g
1 1/4 cups300g
1 1/2 cups360g
2 cups480g
3 cups720g
4 cups960g

Based on USDA FoodData Central data (1 US cup = 240ml = 16 tablespoons = 48 teaspoons). Note: Water is the reference point for all density measurements. 1 cup (240ml) = 240g exactly. All liquid measurements in recipes assume water-like density unless specified. Use water as baseline for density calculations.

About Water Density

The density of water determines how much it weighs per unit of volume. At 1g/ml, 1 US cup (240ml) of water weighs 240g under USDA standard conditions.

Volume measurements can vary by ±10–20% depending on technique (sifted vs. spooned vs. scooped). For consistent baking results, use a kitchen scale with gram measurements whenever possible. The USDA standard (spooned-and-leveled) is the reference point for all values on this page.

Frequently Asked Questions

How many grams is 1 cup of water?

1 cup of water weighs 240 grams (USDA FoodData Central, spooned-and-leveled method, 1 US cup = 240ml).

How many grams is 1/2 cup of water?

1/2 cup of water weighs 120 grams.

How many grams is 1/4 cup of water?

1/4 cup of water weighs 60 grams.

Does measuring technique affect the weight of water?

Yes. Sifted water can weigh up to 20% less than packed or scooped. The USDA standard (spooned-and-leveled) of 240g/cup is the most reliable baseline.

Direct Conversion Pages for Water

Data source: USDA FoodData Central SR Legacy (FDC ID: 14555). View original USDA record

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