Caster Sugar (Superfine):
Grams to Cups
By Stefan Ulrich · Last updated
Caster sugar (also called superfine sugar or bar sugar) weighs 200 grams per cup — the same as granulated sugar. The difference is in particle size, not density: caster sugar has finer crystals that dissolve faster, making it essential for meringues, cocktails, and delicate sponge cakes.
How much Caster Sugar (Superfine) weighs at each cup measure.
Convert Caster Sugar (Superfine)
1 cup = 200 grams
= — grams
= — cups
Quick reference
Measurement Table
| Cups | Grams | Ounces |
|---|---|---|
| 1 tsp | 4 g | 0.14 oz |
| 1 tbsp | 13 g | 0.46 oz |
| ⅛ cup | 25 g | 0.88 oz |
| ¼ cup | 50 g | 1.76 oz |
| ⅓ cup | 67 g | 2.36 oz |
| ½ cup | 100 g | 3.53 oz |
| ⅔ cup | 133 g | 4.69 oz |
| ¾ cup | 150 g | 5.29 oz |
| 1 cup | 200 g | 7.05 oz |
| 1¼ cups | 250 g | 8.82 oz |
| 1½ cups | 300 g | 10.58 oz |
| 2 cups | 400 g | 14.11 oz |
| 3 cups | 600 g | 21.16 oz |
About Caster Sugar (Superfine)
Despite the finer grind, caster sugar and granulated sugar pack to the same weight per cup. This makes substitution straightforward: they are interchangeable by weight in virtually all recipes. The practical difference is that caster sugar dissolves faster — crucial when you're whipping egg whites for meringue or dissolving sugar into cold cocktails.
To make caster sugar at home, pulse granulated sugar in a food processor for 15–30 seconds. Don't over-process — that produces powdered sugar (which is a completely different product with cornstarch added). Aim for visibly finer but still granular crystals.
British recipes frequently call for caster sugar because it's the standard sugar type in UK supermarkets. American bakers can substitute granulated sugar 1:1 by weight with no adjustment needed. The only scenario where caster sugar makes a noticeable difference is in un-baked applications: cold desserts, raw meringues, and whipped cream, where larger granulated crystals may not dissolve completely.
Golden caster sugar (made from unrefined sugar) has a slight caramel flavor and the same weight per cup. It's common in British recipes and adds a subtle warmth that white caster sugar lacks.
Tips for measuring Caster Sugar (Superfine)
- Same weight as granulated sugar: 200 g/cup. Substitute 1:1 by weight.
- Make at home: pulse granulated sugar 15–30 sec in food processor.
- Essential for meringue and cold applications where dissolution speed matters.
- Golden caster sugar = same weight, slight caramel flavor.
Common mistakes
- Over-processing in food processor — turns into powdered sugar, a different product
- Assuming caster sugar is lighter than granulated — same density, different crystal size
Frequently Asked Questions
- How many grams in a cup of Caster Sugar (Superfine)?
- 1 cup of Caster Sugar (Superfine) weighs 200 grams — the standard used in most American recipes. Use the converter above for any other amount.
- How many grams is 1 tablespoon of Caster Sugar (Superfine)?
- 1 tablespoon of Caster Sugar (Superfine) weighs about 13 grams. The full table above lists every common cup fraction.
- What's the most common mistake when measuring Caster Sugar (Superfine)?
- Over-processing in food processor — turns into powdered sugar, a different product. Weighing on a kitchen scale avoids it entirely.
- Do I pack Caster Sugar (Superfine) into the cup?
- Only pack brown sugars; granulated and powdered caster Sugar (Superfine) are spooned in loosely and levelled. Packing the wrong type adds significant weight.