Why flour weight shifts with the type
Flour is milled from wheat, and not all wheat packs the same way. The bran and germ left in whole wheat flour break up the packing, so more air stays in the cup and it weighs less. Cake flour is milled very fine and bleached, which lets it settle into a denser heap than you might expect for something so soft.
All-purpose flour sits in the middle at 120 grams a cup. Bread flour comes in heavier at 127 grams, partly because its protein absorbs moisture and partly because it is milled coarser than pastry flours.
So the spread across four common flours runs from 113 grams to 127 grams a cup. That is a 12 percent swing, and it is why a recipe written for all-purpose flour goes wrong when you swap in whole wheat by volume without adjusting.
The bag lies less than the recipe does
Most flour bags carry a per quarter cup nutrition number, but baking recipes rarely agree with it. Commercial and home bakers have pushed all-purpose flour to 125 grams a cup for years, while the USDA FoodData Central lists 125 grams and many scale-first blogs land on 120.
Both figures are right for the measuring style they assume. Weighing your flour settles it, because 120 grams of all-purpose flour is 120 grams no matter who does the measuring.
One cup of each flour, in grams and ounces
Each ounce figure is the grams per cup divided by 28.349523125, the exact number of grams in an avoirdupois ounce. Grams per tablespoon and teaspoon come from dividing the cup weight by 16 and by 48.
| Flour | 1 cup, g | 1 cup, oz | 1 tbsp, g | 1 tsp, g | 1/2 cup, g |
|---|---|---|---|---|---|
| Whole Wheat Flour | 113 | 3.99 | 7.1 | 2.4 | 56.5 |
| Cake Flour | 114 | 4.02 | 7.1 | 2.4 | 57 |
| All-Purpose Flour | 120 | 4.23 | 7.5 | 2.5 | 60 |
| Bread Flour | 127 | 4.48 | 7.9 | 2.6 | 63.5 |
Sorted lightest to heaviest. Whole wheat and cake flour sit within one gram of each other, yet they behave nothing alike in a dough, which is why density is only part of the story.
Fraction cups and their gram weights
Recipes call for thirds and fifths more than decimal amounts. These are the common fractions for each flour type, rounded to one gram.
| Amount | All-purpose, g | Bread, g | Cake, g | Whole wheat, g |
|---|---|---|---|---|
| 1/4 cup | 30 | 32 | 29 | 28 |
| 1/3 cup | 40 | 42 | 38 | 38 |
| 1/2 cup | 60 | 64 | 57 | 57 |
| 2/3 cup | 80 | 85 | 76 | 75 |
| 3/4 cup | 90 | 95 | 86 | 85 |
| 1 cup | 120 | 127 | 114 | 113 |
| 1 1/2 cups | 180 | 191 | 171 | 170 |
| 2 cups | 240 | 254 | 228 | 226 |
The tablespoon and teaspoon rows you need most. A tablespoon of all-purpose flour weighs 7.5 grams and a teaspoon 2.5 grams. Bread flour runs 7.9 grams a tablespoon and 2.6 grams a teaspoon.
Why the same cup weighs different amounts
Two bakers can measure the same flour into the same cup and get two different weights. The method is the whole game.
Scoop directly into the bag and the cup packs heavier, sometimes 150 grams for all-purpose flour, because you are dragging a load of flour ahead of the cup. Spoon the flour into the cup and level it with a knife and you land near 120 to 125 grams. That is the difference between the two most quoted figures, not an error in either one.
Humidity moves it too. Flour absorbs moisture from the air, and damp flour clumps and weighs more per cup. A 15 gram swing between a dry pantry and a humid summer day is common, and it does not change the grams on a scale.
Questions cooks actually ask
- How many grams is one cup of all-purpose flour?
- About 120 grams spooned and levelled. Recipes and flour mills vary it from 120 to 125 grams, so pick one and weigh to match the recipe you trust.
- Is whole wheat flour heavier or lighter than all-purpose?
- Lighter per cup, about 113 grams against 120. The bran keeps it from packing as tight. That same bran also makes it thirstier, so it drinks more liquid in a dough.
- Why is bread flour heavier than all-purpose flour?
- Bread flour is milled coarser and higher in protein, and both let it settle denser into a cup. A cup of bread flour runs about 127 grams.
- How many tablespoons are in a cup of flour?
- Sixteen, always. The weight of those sixteen varies with the flour, from about 113 grams for whole wheat up to 127 grams for bread.
- Should I measure flour by weight instead of cups?
- For anything with yeast or a precise crumb, yes. A 15 gram swing from scooping is enough to change hydration. A scale removes the argument entirely.
Where these numbers come from
The gram per cup figures follow the spooned and levelled method that scale-first bakers use. All-purpose flour sits at 120 grams a cup here, while USDA FoodData Central lists white all-purpose flour at 125 grams and some flour mills print 120 on the bag.
The ounce conversions divide by the exact 28.349523125 grams in an ounce, computed in code rather than typed, so the table and the tool cannot disagree. Bread flour at 127 grams a cup works out to 4.48 ounces, cake flour at 114 to 4.02 ounces.
- USDA FoodData Central, per cup gram weights for white and whole wheat flour
- NIST Office of Weights and Measures, metric kitchen equivalencies
- Food Standards Australia New Zealand, plain flour density and the 250 ml cup
- The same density set in grams, with the full method Tablespoons to grams Flour grams per cup
- Sugar grams per cup
- Grams to ounces
- Half cup in grams
- Grams to tablespoons
Related converters
These use the same density set and the same method.