Powdered sugar substitutes
Powdered sugar (confectioners' sugar) is granulated sugar ground to a fine powder and blended with a small amount of cornstarch (typically 3% by weight) to prevent clumping. That ultra-fine particle size is what makes it dissolve instantly into frostings and glazes without a gritty texture. Substituting requires matching both the sweetness level and — critically — that fine texture, which is why most swaps involve processing granulated sugar before using it.
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| Rank | Substitute | Ratio (replaces 1 cup Powdered sugar) | Notes |
|---|---|---|---|
| #1 | Homemade blended granulated sugar and cornstarch | 1 cup granulated sugar + 1 tbsp cornstarch, blended in a high-speed blender or food processor for 2–3 minutes, yields approximately 1¾ cups — use 1¾ cups to replace 2 cups powdered sugar | This is the closest functional match; it produces the fine particle size and cornstarch content of commercial powdered sugar, though texture may be slightly less uniform depending on your blender's power. |
| #2 | Superfine sugar (caster sugar) | ¾ cup superfine sugar per 1 cup powdered sugar (superfine is denser; adjust sweetness to taste) | Works reasonably well in cooked applications and some frostings, but lacks cornstarch so it can weep in buttercreams; also doesn't dissolve as readily as true powdered sugar in raw glazes, resulting in slight graininess. |
| #3 | Dry milk powder and granulated sugar blend | 1 cup granulated sugar + 1 tbsp dry milk powder, blended fine, replaces 1 cup powdered sugar | Used in some candy and frosting contexts; the milk powder contributes body and a faint dairy note — works in buttercreams but changes the flavor profile slightly and is not suitable for vegan applications. |
| #4 | Coconut sugar blended fine | 1 cup coconut sugar blended with 1 tbsp cornstarch for 2–3 minutes, replaces 1 cup powdered sugar | Works in a pinch but noticeably worse — it produces a tan-colored, caramel-flavored result and doesn't dissolve as cleanly; acceptable in spiced baked goods or brown-butter glazes where the flavor shift isn't intrusive. |
| #5 | Powdered erythritol or powdered monk fruit sweetener | 1 cup powdered erythritol or powdered monk fruit sweetener replaces 1 cup powdered sugar at a 1:1 ratio by volume | These are the only tested low-sugar options with comparable particle size; erythritol can leave a cooling sensation and both may affect texture in some frostings — use only if a no-sugar-added result is specifically required. |
When to be careful
Meringues, royal icing, and any recipe where powdered sugar's cornstarch content is load-bearing (such as stabilizing a whipped cream frosting for hours) are poor candidates for substitution — the cornstarch level in homemade blends is harder to calibrate precisely, and commercial powdered sugar is milled far finer than a home blender can consistently achieve. Dusting finished pastries for appearance is the one context where texture doesn't matter and any finely blended substitute performs equally well.
Why these substitutes work
Powdered sugar's functionality comes from two factors: particle size and cornstarch. The particles are roughly 50–200 microns, small enough to dissolve in fat or liquid without agitation and fine enough to create a smooth, non-gritty emulsion in buttercreams. The 3% cornstarch is hygroscopic — it absorbs ambient moisture to prevent caking in the package — but in frostings it also contributes a small amount of starch that tightens the structure slightly. Granulated sugar ground at home reaches a comparable (though not identical) particle size after 2–3 minutes in a high-speed blender, which is why that method is the most reliable substitute.
The most reliable path when you’re out of powdered sugar is to blend granulated sugar with cornstarch until it’s fine — it takes about 2–3 minutes in a high-speed blender and gets you close to commercial results in nearly every application. The table above ranks that first for good reason: every other option involves a meaningful trade-off in texture, flavor, or both.
For straightforward glazes and dustings, any of the top three substitutes will be hard to distinguish from the original. Where substitution gets riskier is in stable buttercreams held at room temperature for several hours, or any recipe calling for more than 2 cups of powdered sugar — at that scale, particle-size inconsistency compounds and the final texture can suffer. If powdered sugar is the primary structural ingredient in a recipe, sourcing the real thing is the conservative call.
Frequently asked questions
- Can I use granulated sugar directly in frosting without blending it first?
- Not effectively. Even a few minutes of beating won't fully dissolve granulated sugar in fat-based frostings — the result will be perceptibly gritty. You need to grind it first.
- Does homemade powdered sugar work in royal icing?
- It works acceptably for casual use, but home-blended sugar is rarely as fine as commercial powdered sugar, so royal icing may have a slightly less smooth finish. For intricate decorated cookies where a glass-smooth surface matters, commercial powdered sugar is worth sourcing.
- How long does homemade powdered sugar keep?
- Store in an airtight container at room temperature. Without the anti-caking agents in commercial versions it may clump faster — use within 2–3 weeks and sift before using if it has been sitting.