Powdered Sugar — Cups to Grams

1 US cup of powdered (icing) sugar = 120 grams unsifted. Sifting reduces this to about 100 grams. Always check whether the recipe specifies sifted or unsifted.

Ingredient: Powdered sugar — 120 g per US cup

This calculator uses the US recipe cup (240 ml); the precise customary cup is 236.6 ml.

Powdered sugar — cups to grams

CupsGrams
¼ cup30 g
⅓ cup40 g
½ cup60 g
⅔ cup80 g
¾ cup90 g
1 cup120 g
1½ cup180 g
2 cup240 g

Grams to cups

GramsCups
25 g0.21 cup
50 g0.42 cup
100 g0.83 cup
150 g1.25 cup
200 g1.67 cup
250 g2.08 cup

Note: unsifted; sifted gives ~100 g.

About Powdered sugar

Powdered sugar (also called icing sugar, confectioners' sugar, or 10X sugar) is finely ground granulated sugar with a small amount of cornstarch added to prevent clumping. It is lighter and more prone to compaction than granulated sugar, making precise volume measurement tricky.

The phrase "1 cup, sifted" in older recipes is ambiguous: does it mean sift the sugar then measure one cup (≈ 100 g), or measure one cup then sift it (≈ 120 g)? Most modern bakers interpret it as sift-first-then-measure. For frostings and glazes, where texture matters, weight measurement is strongly preferred: 120 g is unambiguous in a way that "1 cup unsifted" is not.

This converter uses the King Arthur / USDA standard of 120 g per cup unsifted. If your recipe seems to produce too-thick frostings or glazes, consider that the recipe author may have measured sifted sugar and you are adding 20% more. When in doubt, add the powdered sugar gradually until you reach the right consistency.

For baking precision, always weigh ingredients in grams rather than measuring by volume. Ingredient figures are culinary approximations based on King Arthur Baking and USDA references.

Frequently asked questions

How many grams is 1 cup of powdered sugar?

1 cup of powdered sugar (unsifted) equals 120 grams. If the recipe says "1 cup, sifted," it means sift first, then measure — giving about 100 grams.

How many cups is 250 grams of icing sugar?

250 grams of powdered sugar equals about 2.08 cups (unsifted).

Does sifting change how much powdered sugar fits in a cup?

Yes. Sifted powdered sugar is aerated and lighter — 1 cup sifted weighs about 100 g versus 120 g unsifted. The phrase "1 cup, sifted" is ambiguous; most bakers interpret it as sift then measure.

What is confectioners sugar in grams?

Confectioners sugar, powdered sugar, and icing sugar are the same product. 1 cup equals 120 grams unsifted.