One US cup of all-purpose flour weighs 120 grams (about 4 1/4 ounces) according to King Arthur Baking’s ingredient weight chart, the figure most American recipe writers use. The USDA’s FoodData Central lists 125 g for a cup of bleached all-purpose flour. Both are fair averages. The real weight of your cup depends on how the flour got into it, so when a recipe gives grams, weigh.
How many grams is 1 cup of flour? #
Flour doesn’t have one exact weight per cup, because a cup measures volume (236.59 mL in the US) and flour packs down. These are the two published numbers worth knowing:
| Source | 1 cup all-purpose flour | 1 tablespoon |
|---|---|---|
| King Arthur Baking chart | 120 g (4 1/4 oz) | 7.5 g |
| USDA FoodData Central | 125 g | about 7.8 g |
If you’re following a recipe written in cups by an American baker, 120 g is the safer conversion. Most US baking sites and cookbooks that list both cups and grams use it or something very close. If a recipe was developed by weight, it will give you grams directly and you should use them.
The quick mental shortcut #
Remember 1 cup = 120 g, then work from there:
- 1/4 cup = 30 g
- 1 tablespoon = 7.5 g (there are 16 tablespoons in a cup)
- 1 teaspoon = 2.5 g
For whole cups, multiply by 12 and add a zero. Three cups is 36, plus a zero, 360 g.
Cups of flour to grams chart #
All figures use King Arthur’s 120 g per cup, with ounces for bakers whose scale shows avoirdupois ounces.
| Cups | Grams | Ounces |
|---|---|---|
| 1/8 cup (2 tbsp) | 15 g | 0.53 oz |
| 1/4 cup | 30 g | 1.06 oz |
| 1/3 cup | 40 g | 1.41 oz |
| 3/8 cup | 45 g | 1.59 oz |
| 1/2 cup | 60 g | 2.12 oz |
| 2/3 cup | 80 g | 2.82 oz |
| 3/4 cup | 90 g | 3.17 oz |
| 1 cup | 120 g | 4.23 oz |
| 1 1/4 cups | 150 g | 5.29 oz |
| 1 1/2 cups | 180 g | 6.35 oz |
| 2 cups | 240 g | 8.47 oz |
| 2 1/2 cups | 300 g | 10.58 oz |
| 3 cups | 360 g | 12.70 oz |
| 4 cups | 480 g | 16.93 oz |
If your recipe was tested with the USDA’s 125 g figure instead, add about 4%: 2 cups becomes 250 g rather than 240 g. For most cookies, muffins and quick breads, that difference won’t show. For a lean bread dough or a delicate cake, it can.
Why doesn’t a cup of flour have one exact weight? #
A liquid fills a measuring cup the same way every time. Flour doesn’t. It’s a powder full of air, and how much air stays in the cup depends on your technique:
- Dip and sweep. Plunging the cup into the bag packs the flour, so the cup comes out heavier than the chart says.
- Spoon and level. Spooning flour loosely into the cup and scraping the top flat gets you close to 120 g.
- Sifted first. Sifting adds air, so a cup of sifted flour weighs less than a cup of unsifted flour.
Recipes signal this in their wording. “1 cup sifted flour” means sift first, then measure. “1 cup flour, sifted” means measure first, then sift. They are different amounts.
This is why the National Institute of Standards and Technology’s culinary measurement tips call measuring by mass with a kitchen scale “a best practice to improve recipe accuracy.” A digital scale that reads in grams costs less than a good mixing bowl and removes the guesswork entirely.
How much does a cup of other flours weigh? #
Flours vary a lot by grind and protein. King Arthur’s chart gives these weights for one cup:
| Flour | Grams per cup | Ounces per cup |
|---|---|---|
| All-purpose | 120 g | 4 1/4 oz |
| Bread flour | 120 g | 4 1/4 oz |
| Cake flour (unbleached) | 120 g | 4 1/4 oz |
| Whole wheat | 113 g | 4 oz |
| Self-rising | 113 g | 4 oz |
| Pastry flour | 106 g | 3 3/4 oz |
| Medium rye | 106 g | 3 3/4 oz |
| Coconut flour | 128 g | 4 1/2 oz |
| Almond flour | 96 g | 3 3/8 oz |
| Semolina | 163 g | 5 3/4 oz |
| Whole cornmeal | 138 g | 4 7/8 oz |
Swapping flours cup for cup changes the weight you’re adding. A cup of almond flour is 24 g lighter than a cup of all-purpose, and a cup of semolina is 43 g heavier. If you substitute, convert by weight rather than by volume, and expect texture changes anyway.
How do you convert grams of flour to cups? #
Divide the grams by 120. Since nobody owns a 0.833-cup measure, the table below breaks each amount into cup and tablespoon measures you can actually scoop.
| Grams | Cups (decimal) | What to measure |
|---|---|---|
| 50 g | 0.42 | 1/3 cup + 1 1/3 tbsp |
| 100 g | 0.83 | 3/4 cup + 1 1/3 tbsp |
| 125 g | 1.04 | 1 cup + 2 tsp |
| 150 g | 1.25 | 1 1/4 cups |
| 200 g | 1.67 | 1 2/3 cups |
| 250 g | 2.08 | 2 cups + 1 1/3 tbsp |
| 300 g | 2.50 | 2 1/2 cups |
| 400 g | 3.33 | 3 1/3 cups |
| 500 g | 4.17 | 4 cups + 2 2/3 tbsp |
| 1 kg | 8.33 | 8 1/3 cups |
Worked examples #
A cookie recipe calls for 2 1/4 cups of flour. 2.25 × 120 = 270 g. Tare the bowl, spoon flour in until the scale reads 270.
A European bread recipe calls for 500 g of bread flour. 500 ÷ 120 = 4.17 cups. Measure 4 cups, then add 2 2/3 tablespoons (20 g ÷ 7.5 g). Honestly, for bread this is the moment to borrow a scale, because a few spoonfuls either way changes how the dough feels.
You’re halving a recipe that uses 1 2/3 cups. Half is 5/6 cup, which no measuring set has. In grams it’s just 200 ÷ 2 = 100 g.
Converting flour on your phone #
If you bake from a mix of American and metric recipes, Convert Units Calculator has a Cooking category that asks which ingredient you mean before it converts, because a cup of flour and a cup of honey weigh very different amounts. Pick “Flour (all-purpose)” and it shows 120 g per cup on screen, the same King Arthur figure used here, so you can check it against your own reference. It also covers bread flour, whole wheat flour and almond flour among its 26 ingredients. You can type recipe fractions like “1 1/2” or “1½”, and when you convert grams back to cups it shows the nearest measuring-cup mark too: 250 g of flour reads as 2.083333 cups and “2 1/8”. The Cooking category arrived in version 1.0.5, so if your copy doesn’t show it yet, that update hasn’t reached you.
For the same conversion across sugar, butter, oats and the rest, see the cups to grams conversion chart. If the recipe is British or Australian, check how the US cup differs from the UK and metric cups first.
Frequently asked questions #
How many grams is 1/2 cup of flour? #
Half a cup of all-purpose flour is 60 g using King Arthur’s 120 g per cup, or 62.5 g using the USDA’s 125 g figure. For most recipes, 60 g is the number to use.
Is a cup of flour 120 g or 125 g? #
Both numbers are published and both are reasonable. 120 g (King Arthur) matches how most American bakers spoon and level flour. 125 g (USDA) reflects a slightly denser fill. Pick one and use it consistently through a recipe, and prefer whatever gram figure the recipe itself gives.
How many grams is a cup of flour in Australia? #
Australia uses a 250 mL metric cup, which is about 6% bigger than the US cup. Scaling King Arthur’s figure gives roughly 127 g of all-purpose flour per Australian cup. Australian recipes often list grams too, which is the more reliable number.
How many cups are in 1 kg of flour? #
About 8 1/3 US cups at 120 g per cup. A 5-pound bag (2.27 kg) holds roughly 19 cups, so it’s enough for about four or five loaves of sandwich bread.
How many tablespoons of flour are in 100 grams? #
About 13 1/3 level tablespoons, since one tablespoon of all-purpose flour weighs about 7.5 g. Spooning out that many is tedious and error-prone, which is another argument for a scale.