Cups to grams: the complete baking conversion guide

The master table

Every weight below is for a standard US cup (240 ml). If you're following an Australian or UK metric recipe, those cups are 250 ml — multiply the weight by 1.042. British imperial cups are rare in published recipes today, but if you hit one, multiply by 1.183. See our companion post on US vs metric cups for the full story.

Why flour is the worst offender

If you pick one ingredient to weigh and keep everything else in cups, weigh the flour. Flour has enormous built-in variance because it compresses. A scoop from a freshly opened bag, before anything has settled, can hold 150 grams in a cup. That same bag two weeks later, after a dozen openings, may give you 170 grams for the same scoop. The flour didn't change. Gravity did.

The standardized method bakeries use is “spoon and level”: spoon flour into the cup without tapping it, then scrape the top flat with a straight edge. Done carefully, that lands at 125 grams per US cup for all-purpose. The scoop-and-sweep method — using the cup itself like a trowel — packs flour denser and almost always overshoots. Most home bakers do this without realizing. It's why cookies mysteriously turn out dry and tough when you follow the recipe “exactly.”

On a scale, none of this matters. 125 grams is 125 grams whether the bag is new, old, humid, or bone-dry. The variance doesn't disappear in nature — it just stops affecting your bake.

Packed vs unpacked matters more than most recipes admit

Brown sugar is the second-worst offender. “One cup packed” is 220 grams. “One cup lightly spooned” is about 145 grams. A 50% difference depending on a verb the recipe may have omitted. Almost all Western recipes assume packed when they say “brown sugar, 1 cup” — but not all. If your cookies have mysteriously come out thin one batch and cakey the next, sugar packing is a likely culprit.

Powdered sugar is the same story on a smaller scale. “Sifted” drops the weight by roughly 10%. A cup of unsifted powdered sugar weighs about 130 g; sifted, about 115 g. European pastry recipes usually assume sifted; American home recipes usually don't. When in doubt, weigh.

The salt situation

Salt is the ingredient where volume measurements most frequently ruin the dish. A cup of Diamond Crystal kosher salt weighs 142 g. A cup of Morton kosher salt weighs 218 g. A cup of fine table salt weighs 292 g. That's a 2× range for ingredients that all get called “1 tablespoon of salt” in the same recipe.

If a recipe calls for “1 tsp kosher salt” and doesn't specify the brand — which is most recipes — you are already in a range of uncertainty of around 50%. Bread dough with the wrong salt can stall fermentation. A soup can turn inedible. Knowing that a gram of salt is a gram of salt, regardless of crystal shape, solves this class of error entirely.

For bread, the reliable number is a percentage of flour weight, not a volume. A standard lean dough wants 1.8–2.2% salt. The sourdough hydration calculator and pizza dough calculator both output salt in grams directly, using that percentage. No teaspoons involved.

Liquids and the density trick

For water-based liquids, life is simple: 1 cup = 240 g, because water weighs 1 g per ml and a US cup is 240 ml. Milk, buttermilk, thin yogurt, and coffee are close enough to water that the same number works for baking-level precision.

Where it gets interesting is the sugary liquids. A cup of honey weighs 340 g — 40% more than the same volume of water. A cup of maple syrup lands around 312 g. Neutral oils are lighter: a cup of vegetable oil is around 218 g, since oil has a density of roughly 0.91 g/ml. If you're substituting one for another in a recipe, the volume-to-volume swap doesn't preserve the weight, and in enriched doughs that gap matters. Weighing removes the guesswork.

The weighing habit

Here's the practical shift. Buy a $15 kitchen scale with a tare button and a 1-gram resolution. Set the bowl on the scale, tare to zero, add the flour until the number says 500. Tare again. Add the water until it says 350. Tare again. Salt to 10. Starter to 100. You've mixed a loaf in one bowl with zero cups touched. It is faster than the cup method, not slower, because nothing has to be washed between measurements.

The first time this clicks, cup recipes will feel like driving a car without a speedometer. You'll start looking at a recipe in cups and automatically mentally translating it to grams using the table above. After a few dozen bakes the weights memorize themselves. You won't need this page anymore.

If you're converting a lot of recipes in one session, the baking weight converter handles arbitrary cups-to-grams translation for 30+ ingredients in one screen.

References

1. King Arthur Baking Company. Ingredient Weight Chart. kingarthurbaking.com
2. USDA FoodData Central. Food density and composition data for flours, sugars, dairy, and fats. fdc.nal.usda.gov
3. Corriher, S. BakeWise: The Hows and Whys of Successful Baking. Scribner, 2008. Chapter on ingredient measurement methodology.
4. Cook's Illustrated Test Kitchen. The Cook's Illustrated Baking Book. America's Test Kitchen, 2013.
5. Reinhart, P. The Bread Baker's Apprentice. 15th anniversary ed. Ten Speed Press, 2016. Discusses gravimetric vs volumetric measurement for bread.