Ingredient Guide
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Caster Sugar ingredient guide →1 ounce of Caster Sugar in grams
Also known as superfine sugar, castor sugar, baker's sugar.
1 ounce of caster sugar = 28.3 grams. That's based on a 190 g per cup baseline. Use this as a practical baseline for repeatable recipe scaling when packing and crystal size changes between brands.
Answer
28.3 grams
Based on caster sugar density of 0.8 g/ml
Sources: King Arthur Baking, USDA FoodData Central
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Substitute Path
Caster Sugar substitutions
Start with Granulated Sugar using 1:1 by weight, then see the full substitute hub for more tested options.
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Caster Sugar substitute for cookies
Jump straight to the recipe-specific page for ratios and adjustment notes in cookies.
Caster Sugar substitute for cookies →Quick Reference Table
| ounces | grams |
|---|---|
| 1 ounces | 28.3 grams |
| 2 ounces | 56.7 grams |
| 4 ounces | 113 grams |
| 8 ounces | 227 grams |
| 16 ounces | 454 grams |
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Ingredient-specific, density-based conversions for baking
1 ounces of Caster Sugar equals 28.3 grams
Ingredient-specific · density-based
Cup size
Density data from baking references and our own measurements.Advertisement
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.
| Source | Listed measure | Weight |
|---|---|---|
| King Arthur Baking | 1 cup (Baker's Special / superfine) | 190 g |
| King Arthur Baking | 1 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 ounce of caster sugar in grams?
1 ounce of caster sugar is 28.3 grams 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.
Can I use this conversion for recipe scaling?
Yes. This page is built for scaling, but check texture and hydration after the first test batch when packing and crystal size changes.
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.
Other conversions for Caster Sugar
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