Flour Density
Authority: King Arthur Baking Weight Conversion Chart; USDA FoodData Central (dairy items)
Measuring baking ingredients by volume causes up to 25% variation. Standard weight density per 1 US Cup: All-Purpose Flour (120g unsifted), Bread Flour (127g), Cake Flour (114g), Sugar (200g), Brown Sugar (220g packed).
| Ingredient Name | Grams per US Cup (236.6 ml) | Ounces per US Cup | Volumetric Packing Method |
|---|---|---|---|
| All-Purpose Flour | 120 g | 4.25 oz | Spoon and level (unsifted) |
| Bread Flour | 127 g | 4.50 oz | Spoon and level |
| Cake Flour | 114 g | 4.00 oz | Spoon and level |
| Almond Flour | 96 g | 3.38 oz | Lightly spooned |
| Granulated White Sugar | 200 g | 7.05 oz | Direct pour |
| Brown Sugar (Dark/Light) | 220 g | 7.75 oz | Firmly packed |
| Powdered Confectioners Sugar | 120 g | 4.25 oz | Sifted |
| Rolled Oats | 90 g | 3.17 oz | Direct pour |
| Unsalted Butter | 227 g (2 sticks) | 8.00 oz | Packed / solid |
| Heavy Cream (fluid) | 238 g | 8.39 oz | Direct pour (liquid) |
| Sour Cream | 230 g | 8.11 oz | Direct pour (liquid) |
| Buttermilk | 245 g | 8.64 oz | Direct pour (liquid) |
Why Volume Measurement Is Unreliable
A cup is a fixed volume, but flour is a compressible powder -- how much of it fits into that volume depends entirely on how it got there. Scooping a measuring cup directly into a bag of flour packs and compacts it, cramming in significantly more flour by weight than the same cup filled by spooning flour in loosely and leveling it off with a knife.
This is why the flour weights in the table above are tied to a specific technique -- spoon and level for unsifted flour, sifted for confectioners' sugar -- rather than to the cup alone. Two bakers using the same recipe and the same measuring cup can end up with meaningfully different amounts of flour depending on which method they use, which is a common, invisible source of dense or dry baked goods.
Why Recipes Increasingly Use Weight
Weighing ingredients on a kitchen scale sidesteps the packing problem entirely, since a gram of flour is a gram of flour regardless of how it's poured or settled. This is standard practice in professional bakeries and in most European recipes, and it's part of why baking is often described as more exacting than general cooking -- small proportional errors in flour or leavening have an outsized effect on gluten development and rise.
Humidity also affects flour's behavior in ways a scale doesn't fully solve: flour absorbs ambient moisture, so its weight can shift slightly between a dry and a humid kitchen even before water is added, which is one reason experienced bakers still adjust dough by feel alongside the scale.