Sugar: Cups to Grams for Granulated, Powdered, and Brown Sugar
Exact gram weights for a cup of granulated sugar, powdered/icing sugar, and light or dark brown sugar — packed versus loose — with the technique for packing brown sugar correctly.
Sugar seems like it should be simple to measure — it's granular and doesn't compact the way flour does — but the three sugars you'll use most in baking (granulated, powdered, and brown) have meaningfully different densities, and brown sugar adds an entirely separate variable: how hard you pack it into the cup. A loosely-filled cup of brown sugar can weigh 30-40% less than a firmly packed one, which is a huge swing for an ingredient that also controls moisture and chew in cookies. This guide gives you the standard reference weights for each sugar type and explains exactly why 'packed' is not a suggestion when a recipe calls for packed brown sugar — it's load-bearing information about how much sugar the recipe actually wants.
Granulated sugar: 200g per cup
One cup of standard granulated white sugar weighs 200 grams. Because the crystals are uniform and don't compress meaningfully, granulated sugar is one of the more forgiving ingredients to measure by volume — a scooped cup and a spooned-and-leveled cup will usually land within a few grams of each other. This makes 200g/cup a reliable constant to build other conversions from: half a cup is 100g, a quarter cup is 50g, a tablespoon is 12.5g.
Powdered (icing/confectioners') sugar: 120g per cup
Powdered sugar is granulated sugar ground to a fine powder and mixed with a small amount of cornstarch (usually 3%) to prevent clumping, which makes it much lighter and airier by volume — 1 cup weighs only about 120 grams, 40% less than granulated sugar despite being the 'same' sugar. Powdered sugar also compacts and clumps in storage, so sifting before measuring (not after) is important for an accurate cup measurement, especially for glazes and frostings where the sugar-to-liquid ratio determines consistency.
💡 提示： Always sift powdered sugar before measuring by cup — clumped sugar can add 15-20g of hidden weight to what looks like a level cup.
Light and dark brown sugar, packed: 220g per cup
Brown sugar is granulated sugar with molasses added back in — 3.5% for light brown, up to 6.5% for dark brown — and that molasses coating makes the crystals stick together and compress, so a firmly packed cup weighs about 220 grams for either light or dark (the molasses percentage difference isn't enough to change the packed weight meaningfully). Light and dark brown sugar are interchangeable in most recipes by weight; the difference is flavor intensity and moisture, not density.
Why 'packed' isn't optional for brown sugar
When a recipe says '1 cup packed brown sugar,' it means press the sugar into the cup firmly enough that it holds the cup's shape when turned out — this is the only way to hit the 220g reference weight consistently. A loosely spooned cup of brown sugar can weigh as little as 145-160g, a 25-30% shortfall that will measurably dry out cookies, thin a caramel sauce, or reduce the moisture and chew a recipe was designed around. Unless a recipe explicitly says 'lightly spooned,' assume packed is the default for brown sugar.
💡 提示： Test if you've packed it right: turn the cup upside down over your bowl and tap it — a correctly packed cup of brown sugar should hold its shape as a solid block for a second before crumbling.
Why brown sugar clumps and how to fix hardened sugar
Brown sugar hardens when the moisture in its molasses coating evaporates into dry air, letting the sugar crystals bond together into a solid block — it's a moisture problem, not a spoilage problem, so hardened brown sugar is still perfectly usable. Soften it fast by microwaving in 20-second bursts with a damp paper towel draped over the bowl (not touching the sugar), or overnight by sealing it in an airtight container with a slice of bread or an apple wedge, which lets ambient humidity re-absorb into the sugar.
Caster (superfine) sugar and turbinado sugar
Caster sugar, common in UK recipes, has finer granules than standard granulated sugar and packs slightly denser: about 225g per cup versus granulated's 200g. Turbinado (raw, coarse 'sugar in the raw' style) sugar has larger, less uniform crystals that leave more air pockets, weighing closer to 180-190g per cup — useful to know if you're substituting it for granulated in a recipe that depends on precise sugar weight, like a delicate meringue.
常见问题解答
How many grams in a cup of sugar?
It depends on the type: granulated sugar is about 200g per cup, powdered/icing sugar is about 120g per cup (it's much lighter and airier), and firmly packed brown sugar is about 220g per cup. These aren't interchangeable — always check which sugar a recipe means before converting.
Is packed brown sugar the same as regular brown sugar measurement?
No — 'packed' means pressing the sugar firmly into the measuring cup so it holds its shape, which gets you to the standard 220g/cup reference weight. An unpacked, loosely spooned cup can weigh 25-30% less, which will noticeably dry out cookies and other recipes that depend on brown sugar's moisture content.
Can I substitute granulated sugar for brown sugar by cup measurement?
You can substitute by cup in a pinch, but the result will be drier and less chewy since brown sugar's molasses adds moisture that granulated sugar lacks. For a closer match, use granulated sugar by weight and add 1 tablespoon of molasses per cup, which restores both the moisture and the characteristic flavor.
Why does powdered sugar weigh less than granulated sugar per cup?
Powdered sugar is ground much finer than granulated sugar and contains tiny air pockets between its microscopic particles, plus a small amount of anti-caking cornstarch — together these make it about 40% lighter by volume, so 1 cup is roughly 120g versus granulated sugar's 200g for the same cup.
How do I fix hardened brown sugar?
Microwave it in a bowl in 20-second bursts with a damp paper towel loosely covering it (not touching the sugar) until it softens, or leave it overnight in a sealed container with a slice of bread or apple wedge — the sugar reabsorbs ambient moisture and returns to its normal texture within a few hours.
The single biggest sugar-measuring mistake is treating brown sugar like granulated sugar — assuming a loose scoop is fine because 'it's still a cup.' It isn't: packing brown sugar firmly is the difference between 160g and 220g of actual sugar, a swing large enough to change a cookie's texture entirely. Memorize granulated at 200g, powdered at 120g, and packed brown sugar at 220g per cup, and you'll convert almost any baking recipe's sugar measurements correctly.
解放双手来烹饪
在免费的 Bento 应用中获取 AI 膳食计划、逐步烹饪模式和你保存的食谱。
规划饮食、追踪断食、制作购物清单 — 免费
MyCookingCalendar 仪表盘可直接在浏览器中使用，无需下载。