Cups to Grams Converter

Cups measure volume; grams measure mass. Because ingredients have very different densities, there is no single "cup = X grams" rule. A cup of fluffy flour weighs about 125 g, a cup of honey weighs about 340 g — almost three times as much for the same volume. This converter multiplies the number of cups by the standard density for each ingredient (using a US cup of 240 ml).

How the conversion works

The formula is simply grams = cups × grams-per-cup. We use widely accepted reference densities: 125 g flour, 200 g granulated sugar, 220 g brown sugar (lightly packed), 227 g butter, 240 g water and so on. These figures come from King Arthur Baking and the USDA and are the values most American recipe writers calibrate against.

A worked example

A US recipe calls for 2 cups of plain flour and 1½ cups of granulated sugar. In grams that's 2 × 125 = 250 g flour and 1.5 × 200 = 300 g sugar. Weigh those two figures on a kitchen scale and you'll get the result the original recipe writer intended, every time.

Why this matters

UK kitchens work in grams; the world's largest recipe-publishing country works in cups. If you cook from American sources — most food blogs, Bon Appétit, Smitten Kitchen, Joy of Cooking — you need a reliable way to translate. Getting the conversion right is the difference between a tender sponge and a brick, between a balanced sauce and one that's overly sweet. For baking especially, where flour and sugar are structural, accurate weights matter far more than careful technique.

When to use a scale instead

For bread, laminated pastry, macarons and anything where hydration percentage matters, weigh directly in grams and skip the cup step entirely. Even good cup measurements vary by ±10% between cooks; a scale eliminates that variability.

Common mistakes

• Scooping flour straight from the bag, which compacts it and over-measures by 20–30%.
• Using a UK or "metric" cup (250 ml) when the recipe was written with US cups (240 ml).
• Measuring sticky ingredients like honey or peanut butter by volume — they're far easier (and cleaner) by weight.
• Trusting one cup-to-gram value for everything. Density varies by ingredient and even by brand.

Beyond the numbers

Cup measurement grew up alongside a particular style of American home cooking — quick, forgiving, written for the cook with one mixing bowl and a set of nested cups. It works well for casseroles and weeknight bakes, less well for anything where ratios are doing structural work. That's why professional bakers, the BBC Food test kitchen and almost every modern UK cookbook now publish in grams: the same flour, weighed, behaves the same way in your oven as it did in theirs.

Ingredient density also shifts with brand and storage. Flour packed into a sealed bag will weigh more per cup than the same flour after it's sat in a loose jar for a fortnight. Brown sugar dried out at the back of the cupboard is denser still. If you use the same ingredients regularly, weighing once and noting the gram figure on the recipe is faster than re-scooping every time — and it travels with you when you cook the same dish at a friend's house.

Sister tools in the kitchen: Grams to Cups for the return journey, Butter Conversion for sticks and tablespoons, Oven Temperature for the dial, and the Recipe Scaler when the headcount changes.