How many grams in a cup of caster sugar?
One US cup of caster sugar weighs 200 g.
Sold as superfine sugar in the US. Finer crystals than granulated but the same weight per cup.
Every amount a recipe asks for
| caster sugar | In grams |
|---|---|
| ¼ cup | 50 g |
| ⅓ cup | 67 g |
| ½ cup | 100 g |
| ⅔ cup | 133 g |
| ¾ cup | 150 g |
| 1 cup | 200 g |
| 2 cups | 400 g |
Going the other way
If you have a weight and need cups — rounded to the quarter cup, because that is the finest division a cup set actually has:
| 50 g | ¼ cup |
| 100 g | ½ cup |
| 200 g | 1 cup |
| 250 g | 1 ¼ cups |
| 500 g | 2 ½ cups |
| 1000 g | 5 cups |
Which cup does your recipe mean?
“A cup” is four different volumes, so the weight above changes with the recipe's origin. Same caster sugar, same cup measure, different answer:
| Cup | Volume | One cup weighs | Used in |
|---|---|---|---|
| US customary | 237 ml | 200 g | American recipes and measuring cups |
| US legal | 240 ml | 203 g | nutrition labels |
| Metric | 250 ml | 211 g | Australia, New Zealand, Canada |
| Imperial | 284 ml | 240 g | British recipes before roughly 1980 |
200 g per US customary cup. Source: King Arthur Baking ingredient weight chart (superfine sugar). Published values differ by a few grams between references; for anything but bread, a few grams is noise.
Or stop converting by hand
Paste any recipe into RecipeTables and the whole thing converts at once — every ingredient, in one table, with a Cups/Grams switch that remembers which you use. It converts what the author wrote rather than inventing a weight the recipe never gave.
Try it on the recipe you're reading, or read why a cup isn't a cup — four volumes, the 25% flour problem, and the Australian tablespoon that's a third too big.
Convert a whole recipe, free
A link, the text, or a photo of a cookbook page — you get the recipe back as one table. No account needed.