Sugar Conversions: Granulated, Brown and Powdered

Why one cup of sugar is not one weight

A US cup is a measure of volume, and sugar types fill that volume very differently. Fine granulated crystals pack closely, brown sugar is damp and clings together, and powdered sugar is a fine, airy dust that is often mixed with a little starch. The same cup therefore holds about 113 g of powdered sugar and about 213 g of packed brown sugar.

That is why a single “sugar” line in a conversion table is a trap. If a recipe lists granulated sugar in cups, the weight you need is not the weight of a cup of brown or powdered sugar, even though all three are sold in the same aisle and all three taste sweet.

Typical weights per US cup

The figures below use a US cup of 236.588 mL and are typical values, not guarantees:

• Granulated sugar: 198 g (about 7.0 oz)
• Packed brown sugar: 213 g (about 7.5 oz)
• Powdered sugar: 113 g (about 4.0 oz)

Charts differ by a few grams, and some give noticeably different numbers, mostly because of granule size, moisture and how firmly the cup was packed. Treat any chart value as a sensible average and use the weight printed in a recipe whenever it gives one.

Tablespoons, teaspoons and metric cups

Smaller measures follow from the cup. A US cup holds 16 tablespoons or 48 teaspoons, so divide the cup weight accordingly:

• Granulated: about 12.4 g per tablespoon and 4.1 g per teaspoon
• Packed brown: about 13.3 g per tablespoon and 4.4 g per teaspoon
• Powdered: about 7.1 g per tablespoon and 2.4 g per teaspoon

Be careful with “cup” in metric countries. A metric cup is 250 mL, about 5.7% larger than a US cup, so a metric cup of granulated sugar is roughly 209 g, of packed brown sugar roughly 225 g and of powdered sugar roughly 119 g. Check which cup the recipe means before converting; a cooking converter such as this one lets you pick either.

Brown sugar: packed or not

American recipes that call for brown sugar usually assume it is firmly packed into the cup, which is why the chart value of 213 g is higher than a loosely spooned cup would give. Pressing it down with the back of a spoon removes air gaps; the packed cup should hold its shape when turned out.

Packing is also the biggest source of error. Two cooks pressing with different force can end up many grams apart, and a loosely filled cup may hold noticeably less sugar than a hard-packed one. If a recipe says “1 cup packed brown sugar,” weighing about 213 g removes that guesswork. If the recipe says “1 cup brown sugar” with no comment, packing is still the usual assumption, but check the instructions.

Clumpy, hardened brown sugar is a measuring problem too, because lumps leave air pockets. Break them up before measuring or weighing.

Powdered sugar: sifted or not

Powdered sugar is the lightest of the three at about 113 g per cup, and it is the one most affected by technique. Spooning it lightly into a cup gives a low weight; scooping and tapping gives a higher one. Recipes that say “1 cup powdered sugar, sifted” and “1 cup sifted powdered sugar” can mean different things: the first usually means measure, then sift, while the second means sift, then measure.

Because the cup-to-cup variation is large, weight is far more dependable for icing and glazes. A weighed amount of powdered sugar behaves the same however it was packed, and the finished frosting will have the same consistency each time.

Worked examples

Cups to grams. A cookie recipe asks for ¾ cup granulated sugar and ¾ cup packed brown sugar. The granulated part is 0.75 × 198 = 148.5 g, which you can round to 150 g. The brown part is 0.75 × 213 = 159.75 g, or about 160 g. In total that is roughly 310 g of sugar.

Grams to cups. A metric recipe wants 100 g of granulated sugar. Divide by 198 to get 0.505 cups, essentially a half cup. The same 100 g of powdered sugar is 100 ÷ 113 = 0.885 cups, just under 1 cup, while 100 g of packed brown sugar is 100 ÷ 213 = 0.47 cups, close to 7½ tablespoons.

Pounds. A 1 lb bag is 453.6 g, so it holds about 2.3 cups of granulated sugar, about 2.1 cups of packed brown sugar and about 4 cups of powdered sugar. This is useful when a recipe asks for a “bag” or a pound.

Measuring tips

Weighing is the most accurate method for all three sugars: place the bowl on a scale, reset it to zero and add sugar until you reach the target. If you must use cups, use dry measuring cups, fill granulated sugar to the brim and level it with a straight edge, pack brown sugar only when the recipe says so, and spoon powdered sugar in without compressing it.

Never swap sugars by volume and expect the same result. A cup of powdered sugar holds only a little over half the sugar by weight of a cup of granulated, and brown sugar adds moisture and flavor that white sugar does not. When a recipe offers a substitution, follow its stated amounts rather than doing the arithmetic yourself, and always keep the original ingredient list as the final authority.