100 grams of caster sugar is about 8.4 tablespoons. One tablespoon of caster sugar weighs about 11.9 g, and one teaspoon is about 4 g. It is granulated sugar ground one step finer, and that small difference is the whole reason it exists: it dissolves fast enough for meringues and custards, where ordinary sugar leaves a gritty bite.
All figures on this page are approximate, and they come from King Arthur Baking, measured spooned and levelled. Fine-grained white sugar that dissolves faster than granulated sugar. Meringues, cocktails, shortbread and custards. When a recipe has to work the first time, verify with a kitchen scale.
How the measurement works
The figure on this page comes from King Arthur Baking, measured spooned and levelled. One US cup is 16 tablespoons, so every figure here is the cup weight of 190 g divided by 16, rounded to one decimal place. Fine-grained white sugar that dissolves faster than granulated sugar. Meringues, cocktails, shortbread and custards.
All results on this page are approximate. Ingredient weights vary with brand, humidity, temperature and how firmly you pack the spoon, so when a recipe has to work the first time, weigh the ingredient on a kitchen scale and use the numbers here as a guide.
Conversion table
| Amount | Grams of caster sugar |
|---|---|
| 1 teaspoon | 4 g |
| 1 tablespoon | 11.9 g |
| 2 tablespoons | 23.8 g |
| 3 tablespoons | 35.6 g |
| 4 tablespoons | 47.5 g |
| 5 tablespoons | 59.4 g |
| 6 tablespoons | 71.2 g |
| 8 tablespoons | 95 g |
| 10 tablespoons | 118.8 g |
| 12 tablespoons | 142.5 g |
| 1 cup (16 tablespoons) | 190 g |
| 100 g | 8.4 tablespoons |
One tablespoon is one sixteenth of a cup, so every figure above is simply the cup weight divided by 16, rounded to one decimal place. The last row is the headline figure for this page: 100 g of caster sugar is about 8.4 tablespoons. All figures are approximate; verify with a kitchen scale when it matters.
Three real kitchen examples
A pavlova base for a summer dessert
A pavlova base uses 10 tablespoons of caster sugar, about 118.8 g, added a spoonful at a time to whipped egg whites. Caster sugar is the right sugar here because its fine crystals dissolve into the meringue while it whips, instead of sitting in the foam as gritty crystals that weep syrup in the oven. Add the sugar too fast and the meringue collapses; add it spoon by spoon and the pavlova bakes up crisp outside and marshmallowy inside.
Shortbread fingers for afternoon tea
Shortbread made with caster sugar instead of granulated sugar has a finer, more delicate crumb, because the small crystals cream into the butter more evenly. Six tablespoons, about 71.2 g, is the right amount for a small batch, and the sugar should be weighed: a heaped spoon of fine sugar packs far more weight than a level one, and shortbread has so few ingredients that every gram shows.
Sweetening a jug of cold lemonade
Cold lemonade is where caster sugar earns its place: 5 tablespoons, about 59.4 g, stirred into cold lemon juice and water dissolves in seconds, while granulated sugar would sink to the bottom and crunch under the teeth. Stir until the liquid runs clear, then taste and adjust. Because the sugar dissolves completely, the lemonade tastes evenly sweet from the first glass to the last.
Getting it right in your kitchen
Caster sugar matters whenever sugar has to dissolve quickly or cream smoothly. In a meringue, undissolved sugar crystals weep and leave a sticky syrup, and in a custard they leave a gritty texture that no amount of stirring will fix. Caster sugar solves both problems because its crystals are fine enough to dissolve in cold liquid and in whipped egg white. At 190 g per cup it sits just below granulated sugar, so 100 g is about 8.4 tablespoons, and the two sugars are close enough in weight that a swap by weight is simple. By spoonfuls they are not interchangeable: the finer crystals pack more tightly, so a tablespoon of caster sugar weighs about 11.9 g against 12.4 g of granulated sugar, and the same number of spoonfuls gives a different weight.
Scaling with tablespoons is easy once you know the weight of one spoon. To measure 100 g of caster sugar, count out about 8.4 tablespoons, and for 50 g, about 4.2 tablespoons. Halving a recipe that calls for 100 g means using 50 g, and doubling it means 200 g, or about 16.8 tablespoons. The key is to scale every ingredient by the same factor, because changing one ingredient without changing the others throws the recipe out of balance. For large amounts, switch to a cup measure or a scale: counting out more than 16 tablespoons is slow and error-prone, and a cup is faster and more accurate.
Storage. Airtight container, cool and dry, indefinitely.
- Use caster sugar for meringues and cold drinks, where it dissolves fastest.
- Level every spoon, because fine sugar packs easily and heaped spoons over-measure.
- Weigh it for baking; by weight it is close to granulated sugar, by volume it is not.
Frequently asked questions
How many tablespoons is 100 grams of caster sugar?
100 grams of caster sugar is about 8.4 tablespoons, spooned and levelled, using the King Arthur Baking value of 190 g per cup. One tablespoon weighs about 11.9 g. The figure is approximate, so verify with a kitchen scale when the recipe matters.
How many grams is 1 tablespoon of caster sugar?
One level tablespoon of caster sugar weighs about 11.9 g, and one teaspoon is about 4 g. That is slightly less than a tablespoon of granulated sugar, because caster sugar crystals are finer and lighter per cup.
Can I use granulated sugar instead of caster sugar?
Yes, by weight: 100 g of granulated sugar replaces 100 g of caster sugar in most recipes. By volume the swap is less exact, and in meringues and custards the coarser crystals may not dissolve fully, leaving a gritty texture or a weeping meringue. For cold drinks and meringues, caster sugar is worth keeping.
Is caster sugar the same as superfine sugar?
Near enough: American superfine sugar and British caster sugar are both finely ground white sugar with crystals smaller than granulated sugar. The names differ by country, not by product, and both weigh about 190 g per cup. Always confirm with a scale when the recipe is exacting.
How many cups is 100 grams of caster sugar?
100 grams of caster sugar is about 0.53 of a cup, or just over half a cup. A full cup weighs 190 g, so half a cup is 95 g, close enough to 100 g for most recipes. For meringues, weigh the sugar rather than relying on the cup.
Common mistakes to avoid
The most common mistake is using granulated sugar in a meringue and wondering why it weeps: the crystals are too coarse to dissolve fully in the egg white. The second is measuring caster sugar with a heaped spoon, because fine sugar packs easily and a heaped tablespoon can hold half as much again as a level one. The third mistake is buying superfine sugar in the United States and assuming it is the same as British caster sugar: they are near-identical, but always check the weight on a scale rather than assuming. Finally, do not keep caster sugar in a damp cupboard, because its fine crystals clump faster than granulated sugar and the lumps will not dissolve in a cold drink.