Convert Caster Sugar from Teaspoon to Cup (US)
How many US cups is 1 teaspoon of caster sugar?
1 teaspoon of caster sugar (castor sugar) is 0.02 US cups. 2 teaspoons of caster sugar is 0.04 US cups. 1/2 teaspoon of caster sugar is 0.01 US cups. 1/4 teaspoon (0.25 teaspoon) of caster sugar is 0.01 US cups. Use the converter below for any amount.
- These figures use the US cup (240 ml). A metric cup is slightly larger at 250 ml, so it holds a little more.
- Cup sizes are not standard worldwide, so the same cup of an ingredient can weigh more or less depending on the country. What is a cup measurement →
- A teaspoon here is the 5 ml standard, the same in the UK, Europe, and Australia. A US teaspoon is fractionally smaller at about 4.9 ml. When teaspoon size matters →
- A little over or under won't ruin the bake. An extra spoon mainly makes it sweeter.
More about measuring Caster Sugar
Caster Sugar substitutes
Ran out? What to use instead of caster sugar →
No measuring spoons? The tool below gets you close, and a measuring spoon set keeps small amounts accurate.
Nail small amounts, get spoonsCaster Sugar Measurement Converter
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0.02 Cup (US)Caster Sugar Calculators & Baking Tools
Working with caster sugar? These tools handle the jobs a converter cannot.
- Jam and Marmalade Calculator Check the sugar a batch of preserve needs and how many jars it fills.
- Pan Size Converter Rescale a recipe for a different cake tin size.
- Oven to Air Fryer Converter Match the temperature and time when you swap the oven for an air fryer, fan oven, or slow cooker.
- Recipe Scaler Scale any recipe up or down and keep every ingredient in ratio.
Common Caster Sugar Conversions
Here are the most common caster sugar conversions from teaspoons to cups (US).
| Teaspoons | Cups (US) |
|---|---|
| 0.25 tsp | 0.01 cups (US) |
| 0.5 tsp | 0.01 cups (US) |
| 1 tsp | 0.02 cups (US) |
| 2 tsp | 0.04 cups (US) |
| 3 tsp | 0.06 cups (US) |
| 4 tsp | 0.08 cups (US) |
| 6 tsp | 0.13 cups (US) |
| 8 tsp | 0.17 cups (US) |
| 12 tsp | 0.25 cups (US) |
This is a volume conversion, so the result is the same for every ingredient. Use the teaspoons to cups (US) volume converter to switch between cups, tablespoons, teaspoons, and millilitres without weighing.
Frequently Asked Questions
- What is 1 teaspoon of caster sugar in US cups?
- 1 teaspoon of caster sugar is 0.02 US cups. The ratio is fixed, so 2 teaspoons of caster sugar is 0.04 US cups and 0.5 teaspoons is 0.01 US cups. Use the converter above for any quantity, or check the conversion chart on this page for the most common amounts at a glance. Open the caster sugar converter
- How many US cups is 1.5 teaspoons of caster sugar?
- 1.5 teaspoons of caster sugar is 0.03 US cups. The ratio is fixed, so 1 teaspoon of caster sugar is 0.02 US cups and 2 teaspoons is 0.04 US cups. Type any other amount into the converter above for the exact figure, or use the chart above for the common ones.
- What is 2 teaspoons of caster sugar in US cups?
- 2 teaspoons of caster sugar is 0.04 US cups. Conversions scale in a straight line, so halving or doubling a recipe keeps the same ratio. 1 teaspoon of caster sugar is 0.02 US cups, and you can multiply or divide that figure to match whatever your recipe needs. Enter any amount in the converter above for an exact US cups reading.
- How many teaspoons of caster sugar is 0.02 US cups?
- 0.02 US cups of caster sugar is 0.96 teaspoons. The conversion works the same in reverse, so you can switch between US cups and teaspoons without changing the result. This helps when a recipe lists teaspoons but you would rather weigh or measure in US cups. The converter above and the chart above cover both directions for any amount.
- What is 1/2 tsp caster sugar in US cups?
- 1/2 teaspoon of caster sugar is 0.01 US cups. The ratio is fixed, so 1 teaspoon of caster sugar is 0.02 US cups and 2 teaspoons is 0.04 US cups. Half measures come up often when scaling a recipe down, and the figure divides cleanly. Use the converter above for any other amount, or the chart above for the common ones.
Related to Caster Sugar
Sugar
Granulated sugar swaps 1:1 for caster sugar in most recipes, though its larger crystals dissolve more slowly. For meringues or smooth sponges, pulse granulated sugar in a food processor for a few seconds to bring it closer to caster's finer grain. See our Sugar converter.
Icing Sugar
Icing sugar is milled far finer and packs much lighter than caster (125 g vs 225 g per cup), so it is not a 1:1 swap. Use it only where a powder works, such as uncooked frostings and dusting, not for creaming into a cake batter. See our Icing Sugar converter.
Brown Sugar
Brown sugar is caster sugar's opposite in the creaming bowl: damp, clumping, and pressed into the cup instead of levelled off. Swap it in and the molasses brings moisture with it, so a sponge built for caster comes out denser, darker, and slower to dry out. See our Brown Sugar converter.
Raw Sugar
Raw sugar has large, coarse crystals that dissolve slowly, the opposite of fine caster sugar. It packs lighter (200 g vs 225 g per cup), so it is not a 1:1 swap by volume; weigh when substituting. See our Raw Sugar converter.
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