1 gram of Caster Sugar in teaspoons

Also known as superfine sugar, castor sugar, baker's sugar.

1 gram of caster sugar = 0.25 teaspoons. That's based on a 190 g per cup baseline. Because caster sugar can shift with packing and crystal size, weighing is usually more accurate than measuring by volume.

Reviewed by the CupOrGram Editorial TeamSources: King Arthur Baking, USDA FoodData CentralMethodology
Answer
0.25 teaspoons
Based on caster sugar density of 0.8 g/ml
Sources: King Arthur Baking, USDA FoodData Central
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Quick Reference Table

gramsteaspoons
10 grams2.5 teaspoons
25 grams6.3 teaspoons
30 grams7.5 teaspoons
40 grams10.0 teaspoons
50 grams12.5 teaspoons
60 grams15.0 teaspoons
75 grams18.8 teaspoons
100 grams25.0 teaspoons
120 grams30.0 teaspoons
150 grams37.5 teaspoons
200 grams50.0 teaspoons
250 grams62.5 teaspoons
500 grams125 teaspoons

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Ingredient-specific, density-based conversions for baking

1 grams of Caster Sugar equals 0.25 teaspoons
Ingredient-specific · density-based
Cup size
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What the sources say caster sugar weighs

Published values, quoted at the exact measure each source lists. Sources round differently and assume different fill techniques — which is why they rarely agree to the gram.

SourceListed measureWeight
King Arthur Baking1 cup (Baker's Special / superfine)190 g
King Arthur Baking1 cup (granulated, for comparison)198 g

CupOrGram standardizes on 190 g per cup (12 g per tablespoon, 4 g per teaspoon) and uses that single value on every page — how we reconcile the sources.

Why this conversion varies

Caster Sugar can pack very differently depending on crystal shape and moisture.

  • Fine vs coarse crystals change how much fits in a cup.
  • Packed measurements can be much heavier than loose fills.
  • This page uses a consistent 190 g per cup baseline for repeatable conversions.

Why this conversion matters

Caster Sugar directly affects sweetness, spread, and browning. A small conversion mismatch can shift texture and caramelization, especially in cookies and frostings.

Practical baking use

Finely milled granulated sugar — the default baking sugar in the UK and Australia. Sold as superfine or Baker's Special sugar in the US. Use this conversion for cookies, syrups, and frostings where sugar balance affects spread and set.

  • Packed and loose measurements are not interchangeable.
  • Adjust in small steps if your ingredient is unusually moist or dry.

FAQ

How much is 1 gram of caster sugar in teaspoons?

1 gram of caster sugar is 0.25 teaspoons using a 190 g per cup baseline.

Why do caster sugar conversions change between brands?

Caster Sugar can pack very differently depending on crystal shape and moisture. In practice, packing and crystal size can shift results between kitchens.

Is it better to weigh caster sugar for baking?

Usually yes. Weight-based measuring reduces shifts from packing and crystal size, so your results are more repeatable.

Related links for Caster Sugar

Recipe Context for Caster Sugar

For cookies: sugar ratio drives spread and caramelization.

For cakes: sugar level affects tenderness and moisture retention.

For frostings: weight gives repeatable texture batch to batch.

Common Pitfalls

  • Switching brands without re-checking weight can change texture and bake time.
  • Using volume-only measurements for dense ingredients can overshoot recipe targets.
  • Packed vs unpacked sugar measurements are not interchangeable.

Brand Variance Example

Baseline on this page: 1 cup caster sugar = 190g. Real-world range can shift by about 8% because granule size, packing, and moisture level shift how much sugar fits in a cup.

Example for 2 cups: baseline 380g, common range 350g-410g. If your bake is texture-sensitive, start with the lower bound and adjust after a test batch.

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