US Cups to UK Metric Grams Engine
Convert American volumetric cup measurements into exact UK mass in grams calibrated to physical ingredient densities.
Volumetric Conversion Engine
Core Culinary Density Reference Chart
Standard weight equivalents for 1 US Level Cup (240ml standard volume) in metric grams and imperial ounces.
| Baking Ingredient | 1 US Cup (Grams) | 1 US Cup (Ounces) | Density Classification |
|---|---|---|---|
| Plain Flour (All-Purpose) | 120 g | 4.2 oz | Flours |
| Self-Raising Flour | 125 g | 4.4 oz | Flours |
| Strong Bread Flour | 128 g | 4.5 oz | Flours |
| Granulated White Sugar | 200 g | 7.1 oz | Sugars |
| Caster Sugar | 225 g | 7.9 oz | Sugars |
| Icing Sugar (Confectioners) | 125 g | 4.4 oz | Sugars |
| Soft Light Brown Sugar (Packed) | 220 g | 7.8 oz | Sugars |
| Unsalted Butter | 227 g | 8.0 oz | Fats |
| Vegetable / Sunflower Oil | 218 g | 7.7 oz | Fats |
| Whole Milk (Cow's) | 245 g | 8.6 oz | Liquids |
| Golden Syrup / Honey | 340 g | 12.0 oz | Liquids |
| Cocoa Powder (Unsweetened) | 100 g | 3.5 oz | Flours |
Why Culinary Density Cannot Be Universalized
A persistent misconception among international home cooks is that "one cup equals 250 grams." This holds true only for pure liquid water at 4°C, where volume in millilitres matches mass in grams with a density of exactly 1.00 g/ml.
Solid baking ingredients have varied bulk densities determined by crystal dimensions, moisture content, and aerated pockets. Granulated sugar, composed of dense sucrose crystals, weighs roughly 200 grams per cup. Sifted plain flour, which traps substantial air between starch particles, weighs only 120 grams per cup.
Applying a generic "250g per cup" rule to flour introduces double the intended mass, completely throwing off hydration ratios in doughs and batters. Professional bakers always convert volumetric measurements to weight on a digital kitchen scale.