Free cups to grams calculator
Enter a cup amount and pick your ingredient — this cups to grams converter returns the exact weight using density data for flour, sugar, butter, and dozens more ingredients, updated live, as you type.
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Volume-to-weight conversions are approximate and vary by ingredient brand, moisture, and packing method.
Results are estimates. Consult a professional.
How the cups-to-grams calculator works
Cups measure volume — how much space an ingredient occupies. Grams measure mass — how much it actually weighs. Because different ingredients pack differently, the same cup can hold vastly different masses: a cup of honey is nearly four times heavier than a cup of cocoa powder. To convert, the calculator multiplies your cup amount by the ingredient's density expressed in grams per cup.
Worked example: scaling a sandwich-bread recipe
A recipe calls for 2½ cups of all-purpose flour. The baker wants to weigh it for consistency. King Arthur's measured weight for AP flour is 125 g per cup.
Step 1 — Look up the density
All-purpose flour weighs 125 g per cup by King Arthur's spoon-and-level standard. Bread flour (120 g) and cake flour (114 g) are lighter per cup because of their different protein contents and grind sizes.
Step 2 — Multiply
Cups to grams: common baking ingredients
All weights use King Arthur Baking's spoon-and-level method. Brown sugar is packed. Fractions rounded to the nearest gram.
| Ingredient | ¼ cup | ⅓ cup | ½ cup | 1 cup |
|---|---|---|---|---|
| AP flour | 31 g | 42 g | 63 g | 125 g |
| Bread flour | 30 g | 40 g | 60 g | 120 g |
| Cake flour | 29 g | 38 g | 57 g | 114 g |
| Granulated sugar | 50 g | 67 g | 100 g | 200 g |
| Brown sugar (packed) | 55 g | 73 g | 110 g | 220 g |
| Unsalted butter | 57 g | 76 g | 114 g | 227 g |
| Honey | 85 g | 113 g | 170 g | 340 g |
| Cocoa powder | 21 g | 28 g | 43 g | 85 g |
Source: King Arthur Baking ingredient weight chart. Spoon-and-level method throughout.
Tips for converting cups to grams accurately
The gram conversion is only as good as the cup measurement that feeds it. Technique matters as much as arithmetic.
- Spoon and level flour — spoon flour loosely into the measuring cup, then sweep a straight edge across the top. Scooping packs in 20–30 g extra per cup, making the gram target seem too high.
- Pack brown sugar firmly — press until it holds the cup's shape when inverted. All King Arthur brown-sugar weights assume a fully packed cup.
- Weigh sticky ingredients directly — honey, peanut butter and molasses cling to the cup. Place the bowl on a scale, tare to zero, and spoon straight in.
- Scale errors compound at volume — at 4 cups of flour the difference between a correctly spooned cup and a scooped one can exceed 100 g. Switch to a scale for large batches.
- Match the flour type in the calculator — AP, bread and cake flour differ by up to 11 g per cup. Always select the flour your recipe specifies.
Accuracy and limitations
This calculator uses King Arthur Baking's published densities, which are the most widely trusted reference in American recipe development and are measured by professional test-kitchen staff. They represent careful averages across multiple fillings of the same ingredient.
Cup-to-gram conversions are inherently approximate for dry ingredients because real weight depends on how the cup was filled, ambient humidity, and how the ingredient was stored. For professional baking or nutritional-accuracy work, weigh ingredients directly rather than converting from cups.
Baking measurement terms defined
About this cups-to-grams calculator
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