How Many Grams in a Cup of Powdered Sugar?
1 cup = 120g · Tablespoon and teaspoon counts are US volume measures (16 tbsp and 48 tsp per cup). Spoon weights use this ingredient's density.
Quick values
- Cups
- 1
- Tablespoons
- 16
- Teaspoons
- 48
- Grams per tbsp
- 7.5g
- Grams per tsp
- 2.5g
- Grams
- 120
- Ounces
- 4.232879
- Pounds
- 0.264555
Powdered Sugar cups to grams conversion table
| Cups | Tablespoons | Teaspoons | Grams | Ounces |
|---|---|---|---|---|
| 1/4 | 4 | 12 | 30g | 1.05822 |
| 1/3 | 5.333333 | 16 | 40g | 1.41096 |
| 1/2 | 8 | 24 | 60g | 2.116439 |
| 2/3 | 10.666667 | 32 | 80g | 2.821919 |
| 3/4 | 12 | 36 | 90g | 3.174659 |
| 1 | 16 | 48 | 120g | 4.232879 |
| 1.5 | 24 | 72 | 180g | 6.349318 |
| 2 | 32 | 96 | 240g | 8.465758 |
Each US tablespoon ≈ 7.5g · Each US teaspoon ≈ 2.5g
About Powdered Sugar measurements
Powdered sugar, also called confectioners sugar or icing sugar, is granulated sugar ground to a fine powder with a small amount of cornstarch to prevent caking. One US cup weighs approximately 120 grams when sifted and spooned—a fraction of granulated sugar weight because the powder is airy and light. Unsifted powdered sugar in the bag may compact differently.
For frostings and glazes, sift powdered sugar before measuring when recipes call for sifted cups. Spoon the sifted sugar into a measuring cup and level gently without packing. Weighing 120 grams per cup produces smooth buttercream with consistent sweetness and texture across batches.
Mistakes include substituting granulated sugar one-to-one by volume in frostings—it will not dissolve and creates grainy icing. Using unsifted powdered sugar when a recipe specifies sifted adds extra density. Confusing powdered sugar weight with granulated sugar (200g per cup) doubles the sweetener in converted recipes.
Store powdered sugar sealed in a cool, dry place; clumps form from humidity. Break lumps by sifting or pulsing in a food processor. Substitute by grinding granulated sugar with cornstarch in a blender, though commercial powdered sugar is finer and more consistent at 120 grams per cup.
Frostings and glazes depend on powdered sugar's airy 120 grams per cup measurement because excess sugar thickens buttercream past piping consistency. When dusting finished desserts, sifting before sprinkling avoids clumps but is separate from the weight conversion used in batters. American buttercream typically uses four cups of powdered sugar per pound of butter—weighing 480 grams of sugar ensures predictable sweetness. If your powdered sugar bag sat in humid storage, break lumps before measuring or the same cup holds more mass than a freshly opened box.
When piping royal icing, weigh powdered sugar batches in grams so stiff versus flood consistencies repeat identically. Humidity affects flow more than weight, but starting from 120 grams per cup keeps ratios stable.
Frequently asked questions
One cup of sifted powdered sugar equals 120 grams. Unsifted cups may weigh slightly more if compacted.
Sift if the recipe requires it, spoon into a dry cup without packing, and level. Weigh 120g for frosting recipes.
Grind granulated sugar with 1 tsp cornstarch per cup in a high-speed blender. Commercial confectioners sugar is finer and preferred.
Keep sealed in a dry pantry. Sift before use if clumped from humidity. Properly stored, it lasts indefinitely.