How to convert cups to grams
A cup is a volume, so the weight in grams depends on the ingredient's density: grams = cups × density × 236.6 (a US cup is 236.6 mL). One cup of water is about 237 g; one cup of all-purpose flour is about 125 g.
Worked example: two cups of granulated sugar at 0.85 g/mL weigh 2 × 0.85 × 236.6 = about 402 g. The same two cups of all-purpose flour come to only 251 g, which is why swapping one ingredient for another cup-for-cup changes a recipe far more than it appears to.
Handy reference points at one cup: milk (1.03) about 244 g, honey (1.42) about 336 g, butter (0.96) about 227 g, water 237 g.
A quick pass through the cups to mL calculator saves a step later on.
How to use this calculator
Enter the cups and the ingredient density. Density in g/mL: water 1, flour ~0.53, granulated sugar ~0.85, milk ~1.03, honey ~1.42, butter ~0.96. Weighing is more accurate than scooping, especially for flour. Reverse it with the grams to cups calculator.
Density is where most of the error comes from. Scooping flour straight from the bag compacts it and can add 20 to 30 g per cup, so spoon it in and level it off, or better still weigh it. Brown sugar is the opposite case: recipes assume it is firmly packed, which pushes a cup to roughly 220 g rather than the 200 g of loose granulated sugar.
Worth having open at the same time: the cups to pounds calculator.
Frequently asked questions
- How many grams is 1 cup?
- For water, about 237 g. For flour about 125 g and for sugar about 200 g, because densities differ.
- How do I convert cups to grams?
- Multiply cups by the ingredient density in g/mL and by 236.6.
- How many grams is a cup of flour?
- About 125 grams for all-purpose flour.
- Why isn't there one fixed number?
- Cups measure volume; the gram weight changes with each ingredient's density.
- Is a US cup the same as a metric or UK cup?
- No. A US cup is 236.6 mL, a metric cup is 250 mL and the older UK imperial cup is 284 mL. This calculator uses the US cup, so a recipe written with 250 mL cups will weigh about 6% more than the figure shown.