Grams of Powdered Sugar to Cups
Convert powdered sugar grams to cups using the standard unsifted reference of 120 grams per US cup. This page also shows sifted values, recipe wording guidance, sugar substitution warnings, and the texture rules that matter most in frosting and glaze.
Powdered sugar is one of the easiest pantry ingredients to misuse by volume because the sugar is airy, clumps easily, and changes weight when it is sifted. It is also one of the worst sugars to substitute by cups, especially against granulated sugar.
Never substitute powdered sugar for granulated sugar by cups
1 cup of powdered sugar is about 120 grams. 1 cup of granulated sugar is about 200 grams. That gap is large enough to break recipe balance immediately. If you need to compare sugars, compare them by grams.
Powdered Sugar Grams to Cups Calculator
Use the converter below for any amount not listed in the table. It defaults to standard unsifted powdered sugar, which is the safest starting point when the recipe simply says powdered sugar, icing sugar, or confectioners' sugar.
Powdered Sugar Conversion Table
The table below shows both unsifted and sifted cup values. Unsifted powdered sugar uses the common 120 grams per US cupreference. Sifted powdered sugar uses about 110 grams per US cup and should be chosen only when the recipe wording clearly asks for sifted sugar.
| Grams | Cups (unsifted)120g per cup | Cups (sifted)110g per cup |
|---|---|---|
| 15g | 0.13 cups | 0.14 cups |
| 25g | 0.21 cups | 0.23 cups |
| 30g | 0.25 cups | 0.27 cups |
| 50g | 0.42 cups | 0.45 cups |
| 60g | 0.50 cups | 0.55 cups |
| 80g | 0.67 cups | 0.73 cups |
| 100g | 0.83 cups | 0.91 cups |
| 110g | 0.92 cups | 1.00 cups |
| 120g= 1 unsifted cup | 1.00 cups | 1.09 cups |
| 150g | 1.25 cups | 1.36 cups |
| 200g | 1.67 cups | 1.82 cups |
| 240g | 2.00 cups | 2.18 cups |
| 250g | 2.08 cups | 2.27 cups |
| 360g | 3.00 cups | 3.27 cups |
| 500g | 4.17 cups | 4.55 cups |
Unsifted is the default answer on this page. If your recipe clearly expects sifted sugar, compare the numbers with the dedicated sifted powdered sugar page. Need the reverse direction? Use the cups to grams converter.
Sifted vs Unsifted Powdered Sugar
The sifted-versus-unsifted weight gap is not huge compared with some flours, but the texture difference is huge. If you are making buttercream, glaze, or royal icing, the real reason to care is not just grams per cup. It is smoothness, flow, and how predictable the final texture becomes.
Unsifted powdered sugar
- Spooned into the cup and leveled without sifting first.
- May still contain small clumps, especially in humid kitchens.
- This is the safest default when the recipe does not specify sifted.
- Works for basic glaze, dusting, and many everyday frosting recipes.
Sifted powdered sugar
- Passed through a sieve first, which breaks lumps and adds air.
- Produces a lighter cup and a smoother mixing texture.
- Best for royal icing, buttercream, and refined finishing work.
- Most useful when the recipe writer cares about lump-free, softer texture.
How recipe wording changes the answer
Measure the sugar first, then sift it. The measured amount still matches the heavier unsifted cup reference.
Sift the sugar first, then fill the cup. That measured amount matches the lighter sifted cup reference.
Why Powdered Sugar Cannot Be Swapped by Cups
Powdered sugar is one of the worst ingredients to substitute by volume. The fine powder traps air, many products contain a little starch, and the ingredient is built for cold mixing rather than crystal-style creaming. That means two sugars can both look white and sweet while still behaving very differently in the bowl.
Powdered Sugar to Granulated Sugar
1 cup powdered does not equal 1 cup granulated
120g powdered is far less than 1 full cup of granulated sugar
Granulated sugar is much heavier by volume and does not dissolve smoothly in frosting or glaze. If you are forced to adapt, start from grams, not cups.
Granulated Sugar to Powdered Sugar
1 cup granulated can make about 1 2/3 to 1 3/4 cups powdered
200g granulated can be blended into about 200g homemade powdered sugar
Blend granulated sugar with a little cornstarch until very fine. This works for glaze and frosting in a pinch, but homemade powdered sugar is often slightly coarser.
Powdered Sugar to Brown Sugar
Not a useful cup-for-cup swap
Only compare by grams, and only in recipes that can handle molasses
Brown sugar adds moisture, chew, and molasses flavor. It cannot replace powdered sugar in buttercream, royal icing, or smooth glaze.
Powdered Sugar to Caster Sugar
Not 1:1 by cups
Use the same grams only if the recipe can handle a crystal sugar
Caster sugar dissolves more easily than granulated sugar, but it still does not behave like powdered sugar in frostings. It is a conditional substitute, not a direct one.
The golden rule
If you are substituting between sugar styles, compare the original ingredient in grams first. Cup volume tells you almost nothing useful when the sugars differ in crystal size, air content, moisture, or starch content.
How to Measure Powdered Sugar Accurately
Powdered sugar is airy, sensitive to humidity, and easy to compact by accident. That makes measuring technique unusually important, especially when the sugar is the main structure-building ingredient in frosting.
Check whether the recipe says "sifted"
"1 cup powdered sugar, sifted" means you measure first, then sift. "1 cup sifted powdered sugar" means the sugar is sifted before the cup is filled. That wording changes the cup weight, which is why the page shows both unsifted and sifted references.
Break up lumps before measuring
Powdered sugar clumps easily from humidity. Break up visible lumps with a whisk or fork before measuring so the cup does not fill with compacted heavy pockets that make frosting thicker than planned.
Spoon lightly into the cup and level it
Do not scoop directly from the bag and do not pack the sugar down. Spoon it gently into a dry measuring cup, then level the top with a straight edge. That keeps the unsifted cup close to the 120-grams-per-cup reference.
Sift only when the recipe needs smoother texture
Sifting removes stubborn lumps and adds air. It matters most for buttercream, cream cheese frosting, royal icing, and any glaze where visible lumps or extra stiffness would ruin the finish.
Weigh the sugar when texture matters
Powdered sugar can swing frosting texture quickly. A digital scale removes the uncertainty from clumps, scooping pressure, and sifting order. If the recipe is frosting-heavy, grams are the more reliable method.
What Powdered Sugar Does in Baking
Powdered sugar is not just sweeter-looking sugar. The fine texture and starch content help it dissolve without heat, which is exactly why it is so useful in cold frosting, no-bake glaze, and delicate finishing work. Its function is structural as well as sweet.
When powdered sugar goes high, frostings get stiffer and more fragile. When it goes low, glaze turns thin and frosting loses pipeability. That is why this ingredient is better controlled by grams than by visual volume estimation.
Too much powdered sugar stiffens frosting
A high sugar load pulls frosting toward a thick, crack-prone texture that can be hard to spread smoothly.
Too little powdered sugar leaves glaze runny
When the sugar solids are low, glaze sets slowly and may slide off the cake instead of holding a clean finish.
Fine texture lets it dissolve without heat
Powdered sugar dissolves quickly in room-temperature fat or liquid, which is why it is preferred for cold-mixed toppings.
The starch changes texture too
Most powdered sugar contains a little starch, which helps control clumping and subtly supports frosting body.
Powdered Sugar in Common Recipes
These examples give a quick sense of how powdered sugar appears in real frosting, glaze, and finishing formulas. They are also useful sanity checks when you are scaling recipes or trying to spot a typo.
Basic vanilla buttercream
12 cupcakes
Simple powdered sugar glaze
1 loaf cake
Royal icing
24 decorated cookies
Cream cheese frosting
1 layer cake
Dusting for beignets or doughnuts
12 pieces
Powdered sugar shortbread
20 pieces
Lemon drizzle icing
1 loaf cake
Swiss meringue buttercream finish
3-layer cake
Powdered Sugar Grams to Cups FAQ
These questions cover the highest-intent powdered sugar searches, including sifted versus unsifted cups, regional naming, and the substitution mistakes that cause the most recipe failures.
How many cups is 100 grams of powdered sugar?
100 grams of unsifted powdered sugar is about 0.83 cups, which is just under 7/8 cup. If the sugar is sifted before measuring, 100 grams is closer to 0.91 cups. That difference looks small, but it is enough to change frosting thickness and glaze flow in a noticeable way.
How many cups is 200 grams of powdered sugar?
200 grams of powdered sugar is about 1.67 cups unsifted, or roughly 1 2/3 cups. If the sugar is sifted first, the same 200 grams is closer to 1.82 cups. This is a common frosting amount where measuring method and clump control both matter.
How many grams are in 1 cup of powdered sugar?
1 US cup of powdered sugar is about 120 grams when measured unsifted with the spoon-and-level method. If the sugar is sifted before measuring, a cup is closer to 110 grams. That makes powdered sugar much lighter by volume than granulated sugar or packed brown sugar.
What is the difference between sifted and unsifted powdered sugar?
Sifted powdered sugar has been passed through a sieve, which removes lumps and adds air. A sifted cup weighs less than an unsifted cup, but the bigger effect is texture. Sifting is what helps buttercream, glaze, and royal icing stay smooth instead of looking grainy or lumpy.
Can I substitute powdered sugar for granulated sugar by cups?
No. A cup of powdered sugar is far lighter than a cup of granulated sugar and behaves differently because it is finely milled and usually contains a little starch. If you swap them by cups, you change both the sugar amount and the recipe structure at the same time.
What is powdered sugar called in the UK and Australia?
In the UK, Australia, and New Zealand, powdered sugar is usually called icing sugar. In the US, confectioners' sugar is a common alternate name. The naming changes by region, but the basic ingredient is the same fine sugar used for icing, glaze, dusting, and smooth frostings.
How do I make powdered sugar from granulated sugar?
Blend granulated sugar with a little cornstarch until the crystals turn into a very fine powder. The result usually weighs the same as the starting sugar, but the final cup volume is higher because the powder traps more air. Homemade powdered sugar works best as a backup, not a perfect commercial match.
Why does powdered sugar frosting turn out lumpy?
Lumpy frosting usually means the sugar was clumpy before it went into the bowl, or it was added too quickly to cold butter or cream cheese. Sifting helps, but so does breaking up lumps first and adding the sugar gradually. Powdered sugar lumps do not always disappear just because the mixer runs longer.
How many cups is 500 grams of powdered sugar?
500 grams of powdered sugar is about 4.17 cups unsifted, or about 4.55 cups sifted. That is a large frosting-scale amount where grams are much safer than cups. Small measuring errors multiply fast once you are dealing with four or more cups of an airy ingredient.
Does powdered sugar contain cornstarch, and does that matter?
Most commercial powdered sugar includes a small amount of starch to reduce clumping. In frosting and glaze, that usually helps rather than hurts. But it is one more reason powdered sugar is not the same as simply very fine granulated sugar, especially when you start substituting across recipe types.
Related Sugar Conversion Pages
These are the pages people most often need when comparing powdered sugar with other sweeteners, checking a substitution, or following a recipe that names the sugar more precisely.
Powdered Sugar (sifted)
The companion page for recipes that specify sifted powdered sugar before measuring.
Granulated Sugar
Much heavier by cup and the ingredient people most often substitute incorrectly.
Brown Sugar
Even heavier by cup, with extra moisture and molasses that powdered sugar does not have.
Caster Sugar
Finer than granulated sugar, but still a crystal sugar rather than a powder.
Coconut Sugar
Another dry sweetener that cannot take over frosting work cup-for-cup.
Honey
A dense liquid sweetener that belongs in a completely different conversion category.
More Tools
Cups to grams converter
Reverse the calculation when a recipe starts with cups instead of grams.
Printable conversion charts
Browse sugar and pantry charts when you need a quick kitchen-side reference.
Recipe scaler
Scale frosting or glaze recipes without guessing at cup ratios.
Ultimate conversion guide
Compare powdered sugar with flour, syrups, and other baking ingredients in one broader guide.
Using a different sweetener?
Granulated sugar, brown sugar, honey, maple syrup, and other sweeteners all carry very different grams-per-cup values. Pick the exact ingredient before translating a recipe by cups.