Cups of Granulated Sugar (White Sugar) to Grams

The conversion

One US cup of granulated white sugar weighs about 198 grams (King Arthur Baking's standard; most other sources cite 200 g, close enough that the difference is rounding). The conversion is far more reliable than flour because sugar crystals are dense, uniform, and don't pack significantly differently between gentle and aggressive scoops. A loosely-poured cup and a firmly-tapped cup of granulated sugar differ by maybe 2–3%, not the 20% range you see with flour.

Why sugar is forgiving (when granulated is)

The crystals are non-deformable: unlike flour, where pressure changes how much fits in a cup of given volume, sugar crystals don't compress meaningfully. Once the gaps between crystals are filled, there's no more room. This makes volume-to-weight conversions for granulated sugar much more reliable than for any flour or powder.

Brown sugar is the exception. Because brown sugar contains molasses, the crystals stick together and can be packed tightly when pressed. "1 cup brown sugar, packed" can weigh 213 g (the standard); the same cup loosely scooped might weigh only 145 g. Almost all American recipes mean "packed" when they say brown sugar, but the recipe should specify. If it doesn't and the recipe was written before about 2000, assume packed; modern recipes are usually explicit.

Powdered (confectioners') sugar is different

Powdered sugar, or confectioners' sugar, is granulated sugar that's been ground to a fine powder and combined with a small amount of cornstarch to prevent caking. Because the particles are tiny and irregular, the volume-to-weight relationship is less reliable than for granulated sugar. One cup of unsifted powdered sugar is about 113 g (King Arthur); sifted powdered sugar (which has air whipped through it) is closer to 100 g per cup. The 20% difference between sifted and unsifted matters for icings and frostings.

When the precision matters

Caramel and candy-making care about sugar weight more than almost anything else, because the chemistry of the sugar transformation (the conversion of sucrose to caramelized compounds at specific temperatures) depends on exact amounts. A 10% error in sugar can change the final color, flavor, and texture of a caramel sauce.

Bread and yeast doughs care about sugar in a different way: sugar feeds the yeast, and too much sugar slows fermentation. A brioche or enriched bread dough with "doubled sugar" by accident will rise more slowly and produce a different crumb structure. For these recipes, weight measurements are worth the precision.

Most cookie and cake recipes are forgiving enough that a 5% sugar error won't show up in the final product. If you're scaling up a recipe by 50%, the cumulative error from volume measurements gets larger and is worth catching — at large batch sizes, weighing pays off.

The professional preference

Bakeries and professional kitchens weigh almost everything, including sugar. A digital scale that reads to 1-gram precision is the standard tool. The reason isn't sugar specifically — it's that working in weight units makes ingredient ratios visible and makes scaling recipes up or down trivial. Doubling a recipe by weight is a single multiplication; doubling by volume requires you to find the right measuring tools for "1¾ cups + 2 tablespoons."