Convert cups to grams or grams to cups for common baking and cooking ingredients with US, legal, metric, and imperial cup standards plus custom weights.
Cups to Grams Formula
Converting cups to grams uses the density of the ingredient, because a cup is a measure of volume and a gram is a measure of mass. Each ingredient packs a different mass into the same cup, so you multiply by a grams-per-cup figure that is specific to that ingredient.
grams = cups * density
To go the other way, from grams back to cups, you divide:
cups = grams / density
- grams: the mass of the ingredient in grams (g)
- cups: the volume using your selected cup standard
- density: here, an estimated mass per selected cup (g/cup), adjusted from the ingredient reference
The calculator multiplies or divides by an estimated grams-per-cup reference adjusted for your cup size. For custom ingredients, enter both grams per reference cup and that cup’s volume standard. For example, 120 g per 240 mL reference cup corresponds to 125 g per 250 mL cup under the same preparation assumption. Mass ounces and US customary tablespoons are also shown.
Grams per Cup for Common Ingredients
These approximate recipe references match the calculator. Most use the King Arthur Baking weight chart; butter and whole milk use NIST household estimates. Source rounding, preparation and brand matter. Water uses approximately 1 g/mL. Follow the recipe’s gram weight when available.
| Ingredient | Grams per US cup | Mass ounces per US cup |
|---|---|---|
| All-purpose flour, spooned | 120 g | 4.233 oz |
| Granulated sugar | 198 g | 6.984 oz |
| Brown sugar, packed | 213 g | 7.513 oz |
| Powdered sugar, unsifted | 113 g | 3.986 oz |
| Butter | 227 g | 8.007 oz |
| Water (approximately 1 g/mL) | 236.588 g | 8.345 oz |
| Whole milk, fluid | 241 g | 8.501 oz |
| Honey | 336 g | 11.852 oz |
| Oats, old-fashioned or quick | 89 g | 3.139 oz |
| Unsweetened cocoa | 84 g | 2.963 oz |
Example Problems
Example 1. You need 2 US customary cups of spooned all-purpose flour, using the 120 g per cup recipe reference.
grams = cups * density = 2 * 120 = 240 grams.
So 2 cups corresponds to approximately 240 grams with this flour reference.
Example 2. Convert 250 g of granulated sugar using the 198 g per US customary cup reference.
cups = grams / density = 250 / 198 = approximately 1.262626 cups.
This is approximately 1 cup plus 4.202 US customary tablespoons. The reference is an estimate; weigh 250 g when the recipe specifies mass.
FAQ
Why is one cup not always the same number of grams?
A cup measures volume, not weight. Light, fluffy ingredients like flour or oats weigh far less per cup than dense ones like sugar or honey. Because the weight per cup changes with the ingredient, you have to apply that ingredient’s density to get the correct grams.
How many grams are in one cup of flour?
This calculator uses 120 g per US customary cup for spooned all-purpose flour. Different preparation and recipe references can give different weights; use the recipe’s stated grams or weigh the flour.
Is a US cup the same as a metric cup?
A US customary cup is about 236.588 mL; this tool’s metric cup is 250 mL and its imperial half-pint is about 284.131 mL. A US nutrition-label cup is 240 mL. The NIST unit tables distinguish customary volume and mass. Cup-size scaling assumes the same ingredient preparation; recipe weights remain approximate.
