What Can You Use Instead of Powdered Sugar?

If you are out of powdered sugar, the most practical solution is to grind granulated sugar with a small amount of cornstarch. In a food processor or coffee grinder, grind one 200 ml measure of granulated sugar with one 5 ml measure of cornstarch for 1–2 minutes to get a texture close to store-bought powdered sugar. Cornstarch is not just for appearance: powdered sugar tends to absorb moisture from the air, and cornstarch holds some of that moisture and delays clumping. Grinding granulated sugar by itself also works, but it is more likely to absorb moisture and harden sooner.

How do you make powdered sugar at home? Put granulated sugar in a food processor or powerful coffee grinder, add cornstarch equal to one-tenth of the total amount, and grind for 60–90 seconds until it becomes a fine powder. Let the mixture sit in the food processor bowl for a while before opening the lid to prevent the sugar dust from scattering. Sift the mixture as you would store-bought powdered sugar; a fine-mesh sieve will catch any small clumps. If you are using it the same day, you can skip sifting.

Why does the cornstarch ratio matter? Granulated sugar ground without starch also makes a fine powder, but because it is hygroscopic, it can absorb moisture and form small clumps within a few hours. Cornstarch holds some of this moisture and helps keep the sugar free-flowing. This is why homemade powdered sugar can stay in good condition in a jar for weeks. As the starch ratio increases, it can slightly mute the flavor, so it is best not to exceed one-tenth of the mixture. Rice starch works just like cornstarch for people eating gluten-free.

When can you use granulated sugar directly? Sugar mixed into cake and cookie batter dissolves during mixing, so using regular granulated sugar instead of powdered sugar does not change the result. The same is true for creamy fillings where sugar is beaten for a long time with oil or butter, since the grain size no longer matters. The difference appears in decorative uses, such as sifting sugar over a cake or baklava: coarse granules do not make a fine layer, and visible crystals remain on a moist surface before dissolving.

Do liquid sweeteners work the same way? Honey or agave syrup can replace sugar for sweetness, but because they are liquids, they cannot replace powdered sugar for dusting. They can be used to thin a glaze, but they do not work when you want a dusted appearance. Powdered plant-based sweeteners have a similar crystal structure to powdered sugar and can be used for decorating, but most also contain starch, so follow the proportions on the package.

What is the most common mistake? A common mistake is using baking powder instead of cornstarch. Both are white, fine powders, but baking powder can give batter a bitter taste and cause unwanted rising. Another mistake is adding flour instead of starch; ground flour does not become as fine and can leave a faint raw-flour smell in the mixture. Stopping the grinding too soon is another common problem: granulated sugar ground for less than 30 seconds can still feel gritty and will not spread evenly over a cake. Grinding in several short bursts with the lid closed is a safer way to get an even result.

Quick summary. If you are out of powdered sugar, grind granulated sugar with a small amount of cornstarch. The cornstarch makes the texture finer and delays clumping. Granulated sugar also works directly in batter or fillings where it will dissolve. If you need a decorative dusting, liquid sweeteners are not a substitute; choose a powdered alternative and pay attention to the starch ratio.