Cooking Conversions: Cups, Grams, and More
Kitchen · Last updated: July 2025
Kitchen measurement sits at the intersection of volume, mass, and informal tradition. A US recipe might call for “1 cup flour” and “2 tablespoons butter,” while a European recipe lists 250 g flour and 30 g butter. Both can produce excellent food, but converting between them requires knowing which ingredient you are measuring and whether the original author meant US or metric cup sizes.
Volume vs weight in the kitchen
Volume measures space: cups, milliliters, fluid ounces. It works well for liquids—water, milk, oil—because they settle consistently. Weight (mass) measures how much matter is present: grams, ounces, pounds. Weight is superior for dry ingredients whose density varies. A cup of sifted flour weighs less than a cup of scooped-and-leveled flour; the same cup can differ by 30 percent or more. That variability is why serious baking recipes specify grams.
Butter illustrates the confusion: US sticks are labeled in tablespoons and cups, but many scales weigh butter directly in grams. One US stick = 8 tablespoons = ½ cup ≈ 113 g. Margarine and European butters may differ slightly in water content, so for precision baking, weigh it.
US customary kitchen units
| Unit | Equivalent | Metric (approx.) |
|---|---|---|
| 1 tablespoon (tbsp) | 3 teaspoons | 14.79 mL |
| 1 fluid ounce (fl oz) | 2 tablespoons | 29.57 mL |
| 1 US cup | 8 fl oz, 16 tbsp | 236.6 mL |
| 1 US pint | 2 cups | 473 mL |
| 1 US quart | 2 pints, 4 cups | 946 mL |
| 1 US gallon | 4 quarts | 3.785 L |
Australian and Canadian cups are sometimes 250 mL—a metric-friendly standard that still differs from the US 236.6 mL cup. When adapting recipes, confirm which “cup” the author used.
Common ingredient conversions
| Ingredient | 1 US cup (approx.) | Notes |
|---|---|---|
| All-purpose flour (scooped) | 120–130 g | Weigh for accuracy; 125 g is a common standard |
| Granulated sugar | 200 g | More consistent by volume than flour |
| Brown sugar (packed) | 220 g | Must be packed into the cup |
| Water / milk | 240 g | 1 mL water ≈ 1 g at room temperature |
| Honey / syrup | 340 g | Dense; use a liquid cup or scale |
| Butter | 227 g (2 sticks) | 1 stick = 113 g |
Why weight beats volume for flour
Flour is compressible. Scooping with a measuring cup packs more flour into the same volume than spooning flour into the cup and leveling with a knife. Professional bakers and cookbook test kitchens therefore specify flour in grams. King Arthur Baking and other authorities cite roughly 120 g per cup for spooned flour and up to 150 g for firmly scooped flour—a range that can ruin a cake if you guess wrong.
If you own a kitchen scale, use it. If not, learn one consistent method (spoon and level) and stick with it. When converting a US volume recipe to grams, look up the ingredient-specific factor rather than assuming 1 cup = 240 g for everything.
US vs metric baking traditions
American home baking grew up with volume cups and Fahrenheit ovens. European and much Asian home baking uses grams and Celsius. UK recipes often mix both: grams for dry goods, milliliters for liquids, and occasional imperial pints for milk. Japanese recipes frequently list ingredients in grams even for small quantities like baking powder.
Oven temperatures need explicit conversion. Gas mark (UK) is yet another scale. A rough guide: 350 °F ≈ 175 °C (moderate oven); 425 °F ≈ 220 °C (hot). Fan-assisted (convection) ovens cook faster—reduce temperature by about 20 °C or 25 °F when a recipe assumes a conventional oven.
Mass ounces vs fluid ounces
This distinction trips up many cooks. An ounce (oz) of mass is 28.35 g—used for chocolate, cheese, or meat. A fluid ounce (fl oz) is a volume, about 30 mL in the US. Eight fluid ounces of water weigh about eight ounces, but eight fluid ounces of honey weigh considerably more. Never substitute mass ounces for fluid ounces in a recipe.
Scaling and converting recipes
When doubling a recipe, convert everything to one system first. If the original uses cups, convert dry ingredients to grams using a reliable table, multiply, then work in grams. For liquids, milliliters scale linearly. Spices and leavening agents need care—doubling baking soda does not always mean doubling rise; consult baking science resources for large batch changes.
Altitude and humidity affect baking more than small conversion rounding. At high elevation, reduce leavening slightly and increase liquid or oven temperature. Those adjustments are independent of unit choice but explain why two bakers following the “same” converted recipe may still get different results.
Practical kitchen tips
- Buy a scale that toggles between grams and ounces; tare (zero) with the bowl on the scale before adding ingredients.
- Keep a conversion chart inside a cabinet door for tablespoons-to-mL and common cup-to-gram values.
- For liquids, a clear measuring cup with mL and cup markings reduces error.
- When importing recipes from blogs, check the author’s country—“1 cup” without context is ambiguous.
References
Convert cups, grams, ounces, and milliliters on the tounits.com converter.