TidyToolsWhy you can't use one cups-to-grams number
A cup is a measure of volume, but grams measure weight — and different ingredients have very different densities. A cup of flour is about 120 g, but a cup of sugar is around 200 g and a cup of honey is a hefty 340 g. That's why a single conversion factor doesn't work, and why serious baking is far more reliable by weight. This converter uses a typical weight-per-cup for each common ingredient so you get an accurate figure.
Choose your ingredient, pick the direction, and enter the amount to convert between cups, grams, and ounces.
Common conversions (1 US cup)
- Flour ≈ 120 g · Granulated sugar ≈ 200 g · Brown sugar ≈ 220 g
- Butter ≈ 227 g · Water ≈ 237 g · Honey ≈ 340 g · Oats ≈ 90 g
Where these numbers come from
The weights above are typical values. If you want to see the underlying data — and why sources disagree about a cup of flour — we publish the full table: ingredient weights per US cup, 65 ingredients from USDA FoodData Central, with the source record cited on every row. It shows, for example, that brown sugar is 220 g packed but only 145 g unpacked, and that powdered sugar loses 20 g per cup just by being sifted.
Tips
- Weigh where you can — a kitchen scale beats cups for consistent baking.
- Spoon and level flour if using cups; scooping packs it and adds weight.
- Values are typical — brands and how you pack the cup cause small variations.
Frequently asked questions
How many grams is a cup of flour?
About 120 g for plain/all-purpose flour, though it varies a little with how you fill the cup. Weighing is more accurate.
Why does the conversion change by ingredient?
Because a cup measures volume while grams measure weight, and ingredients have different densities — a cup of sugar weighs far more than a cup of oats.
Is a US cup the same as a metric cup?
Close but not identical (a US cup is about 237 ml, a metric cup 250 ml). These values use the US cup, which most recipes assume.