How Many Grams Are in a Cup?

Why does the cup-to-gram conversion change by ingredient?

One cup is a volume measurement (a fixed amount of space), while grams measure mass (weight). The relationship between volume and weight depends on density, which varies wildly by ingredient. A cup of feathers and a cup of lead take up the same space, but the weight in grams differs by thousands. In the kitchen, this means a cup of all-purpose flour weighs about 120 g, while a cup of granulated sugar weighs 200 g, and a cup of honey weighs 340 g, despite all three filling the same 240 ml of space. The denser the ingredient, the more grams per cup. Water serves as the reference standard at exactly 1 g per 1 ml: a US cup of water (237 ml) weighs about 237 g. Anything denser than water weighs more per cup; anything lighter weighs less.

How many grams are in a cup of common dry ingredients?

According to King Arthur Baking's ingredient weight chart, common dry ingredients per US cup: all-purpose flour weighs 120 g, bread flour 120 g, whole wheat flour 113 g, cake flour 113 g, granulated sugar 200 g, brown sugar (packed) 213 g, powdered sugar 113 g, cocoa powder 85 g, oats 89 g, rolled oats 99 g, white rice (uncooked) 185 g, brown rice (uncooked) 175 g, cornmeal 138 g, and salt (table) 255 g. These weights assume properly measured cups: dry ingredients scooped and leveled, never packed (except brown sugar, where packing is the standard). Scooping and leveling gives the standard 120 g per cup of flour; packing it in can add 25-30 g, enough to ruin baked goods.

How many grams are in a cup of liquid?

Liquids weigh different amounts per cup based on density. Water at 1 g per ml weighs about 237 g per US cup. Milk weighs about 245 g per cup (slightly denser than water from milk fat and solids). Heavy cream weighs about 232 g per cup (lighter because of fat content). Honey weighs 340 g per cup (much denser than water from sugar concentration). Maple syrup weighs about 322 g per cup. Olive oil weighs about 216 g per cup (less than water because oil floats). Corn syrup weighs 328 g per cup. Vegetable broth and stocks weigh roughly the same as water at 240 g per cup. Liquids that sink in water (honey, syrup) weigh more per cup; liquids that float (oils) weigh less. For water-based liquids, 240 g per cup is a safe approximation.

How do baking ingredients compare by weight per cup?

For baking, weight measurements give consistent results that volume can't match. Per US cup: butter weighs 227 g (or 8 oz, or 2 sticks, the cleanest conversion in baking), peanut butter weighs 258 g, sour cream weighs 230 g, yogurt weighs 245 g, cream cheese weighs 226 g, chocolate chips weigh 170 g, raisins weigh 145 g, chopped nuts weigh 113 g, and shredded cheese (loose-packed) weighs 113 g. Measuring by cup produces inconsistent results because scooping techniques vary by 20-30 percent; weighing removes that variability. Professional bakers weigh ingredients, and serious home baking books now list both cup and gram measurements.

How do you weigh ingredients without a scale?

Cup measurements are the workaround, but accuracy depends on technique. For flour: spoon flour into the measuring cup gently, then level with a straight edge. Don't scoop the cup directly into the bag, which compacts the flour and adds 20-30 g per cup beyond the recipe's expectation. For brown sugar: pack firmly into the cup until it holds the shape of the cup when turned out; this is one ingredient where packing is standard. For sticky liquids (honey, syrup): coat the measuring cup with oil first so the liquid releases cleanly. For chopped ingredients (nuts, chocolate, fruit): lightly fill the cup without packing. A $15-20 digital kitchen scale eliminates the guesswork and is the single best upgrade for anyone who bakes regularly.

When should you weigh vs measure by cup?

Weighing wins for baking, bread, and pastry where precision affects results. Bread hydration percentages depend on accurate flour-to-water ratios that volume measurement can't deliver. Cookies, cakes, and quick breads also benefit from gram precision. Cup measurements are fine for soups, stews, sauces, casseroles, and most savory cooking where small ingredient variations don't change the outcome. For ingredients used in tiny amounts (spices, leavening, salt, yeast), weighing in grams beats teaspoon measurements because 1 g vs 2 g of salt or yeast can change the dish noticeably. International recipes that list ingredients in grams should be followed by weight; converting to cups introduces error that compounds across the recipe.

How does the US vs metric cup affect grams?

The US cup is 237 ml; the metric cup is 250 ml (5 percent larger). This means gram weights per cup vary by the same 5 percent between systems. A US cup of flour at 120 g becomes a metric cup of flour at about 126 g. For most recipes, this gap doesn't change results meaningfully. For baking where the recipe was developed using one system, using the other introduces about 5 percent more or less ingredient. Australian and Canadian metric cup recipes assume 250 ml per cup; if you're following one with a US cup, you'll come up about 6 g of flour or 10 g of sugar short per cup. The solution is to follow the recipe's gram measurements when listed, or to use the cup system the recipe specifies.

What's the most accurate way to convert recipes by weight?

A digital kitchen scale with 1 g precision is the most accurate method, and a 0.1 g precision scale handles small spice and leavening amounts. To convert any volume-based recipe to weights: look up each ingredient on King Arthur Baking's chart or a similar reference, multiply by the recipe's cup amount, and use the gram figure. Most recipes convert in 5 minutes with a printed reference chart on hand. Many recipe authors now provide weight measurements alongside volume specifically to support this workflow. For recipes that only list volume, online recipe scaling tools can convert automatically if you input the ingredients. The common amounts (120 g flour, 200 g sugar, 227 g butter) get memorized after a few uses.