How Many Cups in a Box of Powdered Sugar?
A 1 lb box of powdered sugar holds about 3 ¾ cups, spooned in unsifted and leveled. A 2 lb bag holds about 7 ½ cups.
Tip: Spoon unsifted powdered sugar into the cup and level it. Sifted, a cup weighs less.
A standard 1 lb (454 g) box of powdered (confectioners') sugar holds about 3 ¾ US cups unsifted, based on 120 g per spooned and leveled cup. A 2 lb bag holds about 7 ½ cups and a 1 kg bag about 8 ⅓ cups. Sifting adds air, so the same box fills more cups when sifted.
Cups of powdered sugar by package size
| Package | Weight | Cups (unsifted) |
|---|---|---|
| 1 lb box | 454 g | about 3 ¾ cups |
| 2 lb bag | 907 g | about 7 ½ cups |
| 1 kg bag | 1,000 g | about 8 ⅓ cups |
| 4 lb bag | 1,814 g | about 15 cups |
How much do you need?
| Use | Powdered sugar | Grams |
|---|---|---|
| Simple glaze for a bundt cake | 1 cup | 120 g |
| Cream cheese frosting for a 9×13 cake | 2–3 cups | 240–360 g |
| Buttercream for a two-layer cake | 3–4 cups | 360–480 g |
| Dusting a cake or brownies | 1–2 tablespoons | 8–15 g |
Measuring powdered sugar
Powdered sugar packs down in the box and forms lumps. Stir or whisk it first, spoon it into the cup without pressing, and level the top. If your recipe says “sifted”, sift before or after measuring exactly as written, because it changes the amount.
The converter above is set to a 1 lb box (454 g). See the powdered sugar grams to cups chart for every amount.
Questions
How many cups are in a 1 lb box of powdered sugar?
About 3 ¾ cups, unsifted, spooned and leveled.
How many cups are in a 2 lb bag of powdered sugar?
About 7 ½ cups, unsifted.
How many cups is 16 oz of powdered sugar?
16 oz is 1 lb (454 g), which is about 3 ¾ cups unsifted.
How much powdered sugar do I need to frost a cake?
A typical American buttercream for a two-layer 8- or 9-inch cake uses 3–4 cups, so about one 1 lb box. Cupcakes for 24 use a similar amount.
Does sifted powdered sugar measure more cups?
Yes. Sifting fills the sugar with air, so the same weight takes up more room. If a recipe asks for sifted cups, sift first, then spoon into the cup.