Cooking Measurement Conversions: Cups, Grams and Millilitres

Cooking measurement systems are a global headache. North American recipes use cups, tablespoons and fluid ounces. European and Australian recipes use grams and millilitres. British recipes sometimes use imperial ounces, which differ from US fluid ounces. Following a recipe from a different country often requires converting between systems that were never designed to be compatible.

Volume vs Weight: The Core Problem

The fundamental issue is that cups measure volume while grams measure weight. For liquids, the conversion is consistent: one cup of water is always approximately 237 millilitres (in US measurements) regardless of what liquid it is. But for dry ingredients, volume and weight diverge dramatically. One cup of all-purpose flour weighs about 125 grams. One cup of sugar weighs about 200 grams. One cup of cocoa powder weighs about 85 grams. The same volume contains very different weights depending on the ingredient's density.

This is why professional bakers and chefs worldwide prefer weight measurements. A recipe that calls for 250 grams of flour is unambiguous. A recipe that calls for 2 cups of flour depends on how tightly the flour is packed, whether it was sifted, and whether the cook scoops the cup into the flour bin or spoons flour into the cup. These variations can change the actual flour quantity by 20 percent or more.

Common Conversion Reference Points

Some conversions appear so frequently that they are worth memorizing:

• 1 US cup = 237 ml (often rounded to 240 ml)
• 1 Australian cup = 250 ml
• 1 UK imperial cup = 284 ml (rarely used in modern recipes)
• 1 tablespoon = 15 ml (US and international) or 20 ml (Australian)
• 1 teaspoon = 5 ml (universal)
• 1 fluid ounce (US) = 29.6 ml
• 1 fluid ounce (UK) = 28.4 ml
• 1 ounce (weight) = 28.35 grams
• 1 pound = 453.6 grams

Note the Australian tablespoon difference. Australian recipes using tablespoons assume 20 ml, not 15 ml. This discrepancy is small per tablespoon but compounds significantly in recipes calling for several tablespoons of a potent ingredient like baking powder.

Temperature Conversions

Oven temperatures present another conversion challenge. North American recipes use Fahrenheit. Most other countries use Celsius. Gas mark numbers, still common in British recipes, add a third system. The conversion formula between Fahrenheit and Celsius is not intuitive: subtract 32, then multiply by 5/9 to go from Fahrenheit to Celsius. Or multiply by 9/5 and add 32 to go the other direction.

Common baking temperatures to remember: 350 degrees Fahrenheit equals 175 degrees Celsius (Gas Mark 4). 400 degrees Fahrenheit equals 200 degrees Celsius (Gas Mark 6). 450 degrees Fahrenheit equals 230 degrees Celsius (Gas Mark 8).

Butter Measurements

Butter in North American recipes is measured in sticks, cups or tablespoons. One US stick of butter is 113 grams, half a cup, or 8 tablespoons. European recipes specify butter in grams. Australian recipes may use grams or tablespoons. Since butter density is consistent, these conversions are reliable once you know the reference values. But the number of different ways to express the same quantity of butter illustrates why a conversion tool is so useful.

Why Precision Matters in Baking

In savory cooking, measurement imprecision is forgiving. An extra tablespoon of olive oil or a slightly heavier hand with the garlic rarely ruins a dish. Baking is different. The ratios of flour, sugar, fat and liquid determine the chemical reactions that create texture, rise and structure. A 10 percent error in flour quantity can turn a tender cake into a dense brick or a puddle that never sets. For baking, always convert to weight measurements when possible and use a kitchen scale.

For quick and accurate conversions between any cooking units, a cooking converter handles the ingredient-specific density lookups that make cup-to-gram conversions reliable — so you can follow any recipe from any country without second-guessing the measurements.