Precision unit conversion
US recipes measure by volume (cups), UK recipes measure by weight (grams) — here's how to bridge the gap without ruining a bake.
The single biggest source of kitchen conversion frustration is the US cup. It isn't just that the measurement is unfamiliar in the UK — it's that a "cup" of flour and a "cup" of sugar don't weigh the same amount, because a cup measures volume, not mass, and different ingredients pack differently.
UK (and most European) recipes sidestep this problem entirely by measuring dry ingredients in grams on a kitchen scale, which is far more precise and repeatable than scooping a cup of flour, which can vary by 15–20% in weight depending on how it's packed. This is why converting a US recipe properly usually means converting to grams, not just swapping cups for millilitres.
| Convert | Result |
|---|---|
| 1 US cup plain flour | ≈ 120–125g |
| 1 US cup granulated sugar | ≈ 200g |
| 1 US cup butter | ≈ 227g (2 sticks) |
| 1 US cup milk or water | ≈ 237ml |
| 1 US tablespoon | ≈ 15ml |
| 1 US teaspoon | ≈ 5ml |
These are approximate because flour, sugar and similar dry ingredients compress differently depending on how they're scooped — for genuinely accurate baking, a kitchen scale and gram measurements will always beat a converted cup measurement.
A US fluid ounce (29.5735ml) and a UK fluid ounce (28.4131ml) are different sizes, and a US pint (16 US fl oz) is smaller than a UK pint (20 UK fl oz). If a recipe calls for "1 pint" without specifying, check the source country before assuming which pint it means — the difference is large enough to throw off a sauce or batter.
Roughly 120–125g for plain (all-purpose) flour, though this varies with how the flour is scooped — spooning flour into the cup and levelling it gives a more consistent result than scooping directly from the bag.
No — a UK pint is 568ml while a US pint is 473ml, about a 20% difference.