Kitchen Converter & Portions Scaler

Volume measures space, weight measures mass, and the conversion between them depends entirely on what you are measuring. A cup of water is about 240 grams, a cup of flour about 120, a cup of honey about 340. A single conversion factor cannot be right for all three, which is why this converter asks which ingredient you mean.

Flour is the ingredient that punishes this most. Scooping the cup directly into the bag compacts the flour and can yield 150 grams where the recipe intended 120, a difference of a quarter. That is the usual explanation for a cake that came out dense when the method was followed exactly.

The cup itself is not standard either. A US cup is roughly 237 millilitres, a metric cup 250, and an imperial cup 284. Recipes rarely say which they mean, so weight is the only unambiguous way to write down a quantity.

Most ingredients scale linearly and can be multiplied without thought. Several do not. Salt, spices, and anything strongly aromatic should be scaled to around three quarters of the multiplier and then adjusted to taste, because perceived intensity does not track quantity.

Baking time does not scale at all. Doubling a cake mixture and putting it in one tin gives you a deeper cake that needs a lower temperature and considerably longer, not double the volume in the same time. Two tins at the original time is the safer approach.

Oven temperatures convert cleanly between Celsius and Fahrenheit, but gas marks do not map exactly, and fan ovens generally run about twenty Celsius hotter than the dial suggests.