Grams vs Cups for Baking
A cup is a measure of space, not of substance. For most cooking that is fine. For baking it is the difference between a soft cookie and a dry one.
The problem with a cup of flour
Flour compresses. How much ends up in a cup depends entirely on how it got there. Dip the cup straight into the bag and press it down and you can end up with around 150 g. Spoon it in loosely and level the top and it is closer to 120 g.
That is a swing of roughly 25 per cent from the same cup. In a recipe calling for two cups, it is the difference between 240 g and 300 g of flour — an extra 60 g that the liquid in the recipe was never meant to hydrate. It is the most common cause of dry cookies, dense muffins and tough bread, and it is completely invisible while it is happening.
This is why every recipe on this site gives both. Cups are convenient and familiar. Grams are unambiguous. Use whichever suits your kitchen, but if a bake keeps going wrong in the same way, the scale will usually tell you why.
Where it matters most
| Matters a lot | Matters little |
|---|---|
| Flour in any bake | Vegetables in a stew |
| Cocoa powder, which compacts badly | Stock and broth |
| Brown sugar, where "packed" is doing real work | Herbs and aromatics |
| Gluten-free blends, which vary more than wheat | Anything simmered to taste |
| Yeast and raising agents in small quantities | Toppings and garnishes |
Baking is chemistry with fixed ratios. Cooking mostly is not. Nobody needs to weigh an onion.
Common weights, and why they are still approximate
These are the figures used across this site. Published conversions vary between sources, which is itself an argument for weighing.
| Ingredient | 1 cup, approximately |
|---|---|
| All-purpose flour | 120–130 g, spooned and levelled |
| Bread flour | 120–130 g |
| Granulated sugar | 200 g |
| Brown sugar, packed | 200 g |
| Icing sugar | 120 g |
| Cocoa powder | 85 g |
| Rolled oats | 90 g |
| Butter | 225 g |
| Milk or water | 240 g |
| Honey | 340 g |
Note the last two. A cup of water weighs 240 g and a cup of honey weighs 340 g. Volume and weight are only interchangeable for things with the density of water, which is why measuring jugs work for milk and mislead for syrup.
If you are measuring by cup, do it this way
- Stir the flour in its container first — it settles and compacts as it sits.
- Spoon it lightly into the cup rather than scooping with the cup.
- Level the top with the back of a knife. Do not tap or press.
That method lands close to 120 g per cup, which is what most recipes assume. The scoop-and-pack method is what gives you 150.
On buying a scale
A digital kitchen scale costs about the same as a couple of bags of good flour, and the practical benefit is not precision so much as fewer dishes: you can weigh straight into the mixing bowl, pressing tare between each ingredient, and never wash a measuring cup again.
Recipes where weighing makes the most difference
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