Quick answer: One US cup of plain (all-purpose) flour weighs about 120 g when the flour is spooned into the cup and levelled. Half a cup is 60 g and a quarter cup 30 g. Self-raising and wholemeal flour are a little lighter, at about 113 g per cup. Scooping straight from the bag packs in more, so weighing is safer.
Flour is the ingredient where cup measurements cause the most trouble, because it compresses so easily. The same cup can hold quite different amounts depending on how you fill it. This chart gives gram weights for the flours you are likely to buy in a British supermarket. For other conversions, such as spoons and oven temperatures, browse the UK cooking measurements section.
How many grams of flour are in a cup?
A cup of plain flour is 120 g, which is about 4¼ oz. That figure comes from the King Arthur Baking ingredient chart, one of the most widely used American references, and assumes the spoon-and-level method. You will also see 125 g quoted in some recipes; the difference is small enough that either works for cakes and biscuits.
Cups to grams flour converter
US cups= gCups to grams flour chart
Read across from the cup measure in your recipe to the flour you are using. Weights are rounded to the nearest gram; the ounce column is for plain flour.
| US cups | Plain or strong white flour | Self-raising or wholemeal flour | Plain flour in ounces |
|---|---|---|---|
| ⅛ cup (2 tbsp) | 15 g | 14 g | 0.5 oz |
| ¼ cup | 30 g | 28 g | 1.1 oz |
| ⅓ cup | 40 g | 38 g | 1.4 oz |
| ½ cup | 60 g | 57 g | 2.1 oz |
| ⅔ cup | 80 g | 75 g | 2.8 oz |
| ¾ cup | 90 g | 85 g | 3.2 oz |
| 1 cup | 120 g | 113 g | 4.2 oz |
| 1½ cups | 180 g | 170 g | 6.3 oz |
| 2 cups | 240 g | 226 g | 8.5 oz |
| 2½ cups | 300 g | 283 g | 10.6 oz |
| 3 cups | 360 g | 339 g | 12.7 oz |
| 4 cups | 480 g | 452 g | 16.9 oz |
Two cups of plain flour weigh 240 grams, just under half of a standard 500 g bag. Four cups come to 480 g, so a 1.5 kg bag holds a little over twelve cups.
Does every type of flour weigh the same per cup?
No. Coarser, oilier or more finely milled flours pack differently, so a cup can range from under 100 g to over 160 g. The UK names below are matched to the American products in the King Arthur chart.
| Flour (UK name) | US name | Grams per US cup |
|---|---|---|
| Plain flour | All-purpose flour | 120 g |
| Strong white bread flour | Bread flour | 120 g |
| Self-raising flour | Self-rising flour | 113 g |
| Wholemeal flour | Whole wheat flour | 113 g |
| Type 00 pasta and pizza flour | ’00’ flour | 116 g |
| Spelt flour | Spelt flour | 99 g |
| Ground almonds | Almond flour | 96 g |
| Gram flour | Chickpea flour | 85 g |
| Rice flour | White rice flour | 142 g |
| Cornflour | Cornstarch | 112 g |
| Semolina | Semolina flour | 163 g |
How many cups is 100 g of flour?
100 g of plain flour is about ⅚ of a cup, or ¾ cup plus 1 tablespoon and 1 teaspoon. The reverse chart below uses 120 g per cup, 7.5 g per US tablespoon and 2.5 g per teaspoon, which is handy if you own cup measures but no scales. If you have neither, the guide on measuring 100 g of flour without scales uses everyday spoons instead.
| Plain flour | US cups (decimal) | Practical measure |
|---|---|---|
| 100 g | 0.83 | ¾ cup + 1 tbsp + 1 tsp |
| 125 g | 1.04 | 1 cup + 2 tsp |
| 150 g | 1.25 | 1¼ cups |
| 200 g | 1.67 | 1⅔ cups |
| 250 g | 2.08 | 2 cups + 1 tbsp + 1 tsp |
| 300 g | 2.50 | 2½ cups |
| 500 g | 4.17 | 4 cups + 2 tbsp + 2 tsp |
How do you measure a cup of flour accurately?
Fluff, spoon, level: never press the cup into the bag. If you are following an American recipe with cup measures, this method gets you closest to the 120 g the recipe writer most likely intended.
- Loosen the flour. Stir it in the bag or tub with a spoon so it is not compacted.
- Spoon it into the cup. Keep going until it forms a loose mound above the rim. Do not tap or shake the cup.
- Level the top. Sweep the back of a knife across the rim once.
Sifting before measuring makes a cup lighter still, so only sift first if the recipe says “1 cup sifted flour”. If it says “1 cup flour, sifted”, measure first and sift afterwards.
Where are cup measures used, and are they all the same?
The charts on this page assume the US cup of 236.6 ml, which is what American recipes mean. Australian and New Zealand recipes use a 250 ml metric cup, which holds about 6% more, so a cup of plain flour measured the same way comes to roughly 127 g. Older British recipes that mention a cup are rarer and often meant a teacup or half an imperial pint, so check the recipe’s origin.
In the UK, cups mainly turn up in American cookbooks, food blogs and recipe videos. For the full process of converting those recipes, including butter, liquids and oven temperatures, see how to convert American recipes to UK measurements.
Frequently asked questions
How many grams is 1 cup of plain flour in the UK?
One US cup of plain flour is about 120 g when spooned in and levelled. Some recipes use 125 g, and a cup scooped straight from the bag will weigh more.
How many grams is half a cup of flour?
Half a US cup of plain flour is about 60 g. Half a cup of self-raising or wholemeal flour is about 57 g.
Is a cup of self-raising flour the same weight as plain flour?
It is slightly lighter, at about 113 g per US cup compared with 120 g for plain flour. The difference only matters in large quantities.
How many cups are in a 1.5 kg bag of flour?
A 1.5 kg bag of plain flour holds about 12½ US cups at 120 g per cup.
Should I use cups or scales for baking?
Scales are more accurate, because the weight of a cup of flour depends on how it is filled. Cups are fine if you use the spoon-and-level method consistently.
Sources
- King Arthur Baking: ingredient weight chart (gram weights per cup)
- NIST: US customary to metric conversions (cup volume)