Caster Sugar — Cups to Grams

1 cup of caster sugar = 200 grams

1 cup of caster sugar weighs approximately 200 grams. Use the converter below for custom amounts, or check the full conversion table.

Caster Sugar Converter

Result

200 g

Why Does Caster Sugar Weigh 200g Per Cup?

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Caster sugar is denser than flour but lighter than water. Its fine, uniform crystals pack more efficiently than granulated sugar, which is why the same volume weighs slightly more. Unlike flour, sugar doesn't compress much when scooped, making cup measurements more reliable — but still not as accurate as weighing.

A cup of caster sugar weighs about 200g — nearly twice as much as a cup of flour (125g), but less than a cup of honey (340g). The fine crystals dissolve faster than granulated sugar, which is why it's preferred for baking.

When Does Precision Matter for Caster Sugar?

Sugar precision matters most in delicate baked goods where it affects structure, not just sweetness. In meringues and macarons, the sugar-to-egg-white ratio is critical — too little sugar and meringue won't hold peaks; too much and it becomes grainy. In caramel and candy-making, precision is essential for reaching correct temperatures. For cookies and cakes, being off by 10-15% usually won't ruin the recipe, though it affects texture and browning. In beverages, sauces, and fruit desserts, precision matters least — adjust to taste.

How to Measure Caster Sugar Correctly

Caster sugar should be measured by spooning it into the measuring cup and levelling it off. Unlike brown sugar, it should not be packed. For the most accurate measurements, especially in delicate recipes like meringues or sponge cakes, use a kitchen scale. The fine texture means it can settle, so give it a light stir before measuring if it's been stored for a while.

Understanding Caster Sugar Measurements

Caster sugar (also called superfine sugar) is finely granulated sugar that dissolves quickly, making it ideal for baking. One cup of caster sugar weighs approximately 200 grams. Its fine texture means it measures differently than regular granulated sugar, though the weight per cup is similar.

Common Uses in Baking & Cooking

Caster sugar is preferred in recipes where quick dissolution is important, such as meringues, sponge cakes, and custards. It's also excellent for making syrups and sweetening beverages. In the UK, caster sugar is the standard for most baking, while in the US, regular granulated sugar is more common but can often be substituted. If you need a substitute, see our Caster Sugar substitution guide.

Storage and Handling Tips

Store caster sugar in an airtight container in a cool, dry place. It has a long shelf life and doesn't require refrigeration. If it becomes clumpy due to humidity, you can break it up with a fork or process it briefly in a food processor.

Need to convert caster sugar to other units? Try our cups to grams converter or tablespoons to grams converter.

Related Guides

Related Ingredients

Caster Sugar Conversion Table

AmountGramsOunces
1 teaspoon4.17g0.15 oz
1 tablespoon12.5g0.44 oz
¼ cup50g1.76 oz
⅓ cup66.7g2.35 oz
½ cup100g3.53 oz
⅔ cup133g4.7 oz
¾ cup150g5.29 oz
1 cup200g7.05 oz
1½ cups300g10.6 oz
2 cups400g14.1 oz

Caster Sugar — US, Metric & UK Cup Conversions

Cup sizes vary by country. This table shows how much caster sugar weighs when measured with US cups (most online recipes), metric cups (Australia, NZ, Canada), or UK/Imperial cups.

AmountUS Cup(236.6 ml)Metric Cup(250 ml)UK Cup(284 ml)
¼ cup50g52.8g60g
⅓ cup66.7g70.4g80.1g
½ cup100g106g120g
⅔ cup133g141g160g
¾ cup150g159g180g
1 cup200g211g240g
1½ cups300g317g360g
2 cups400g423g480g

Note: US cups (236.6 ml) are standard in most online recipes. Metric cups (250 ml, used in Australia, NZ, Canada) hold 5.7% more. UK/Imperial cups (284 ml) hold 20% more than US cups.

Need a Substitute?

Out of caster sugar? We've got 3 tested alternatives with exact ratios.

Granulated Sugar(1:1)
Coconut Sugar(1:1)
Honey(¾ cup per 1 cup sugar, reduce liquid)
See all alternatives for Caster Sugar

Frequently Asked Questions

Can I substitute granulated sugar for caster sugar?
Yes, in most recipes. Granulated sugar has larger crystals that dissolve more slowly, which can leave a slightly grainy texture in delicate items like meringues or sponge cakes. For cookies, cakes, and most baking, the substitution works fine. You can also make caster sugar by pulsing granulated sugar in a food processor for 30 seconds.
Why do UK recipes use caster sugar instead of regular sugar?
Caster sugar is the British baking standard because its fine texture dissolves quickly and creates lighter, more tender baked goods. American "granulated sugar" has larger crystals. For most recipes, they're interchangeable, but caster sugar gives better results in meringues, sponges, and anything requiring quick dissolution.
How many grams is 1 cup of caster sugar?
One US cup of caster sugar weighs approximately 200 grams. In a metric cup (250ml), it's about 212g. In a UK Imperial cup (284ml), it's about 240g. The fine crystals pack consistently, making caster sugar one of the more reliable ingredients to measure by volume.
What's the difference between caster sugar and powdered sugar?
Caster sugar is finely granulated but still crystalline. Powdered sugar (icing sugar) is ground to a powder with added cornstarch to prevent clumping. They're not interchangeable — powdered sugar dissolves instantly and creates different textures. Use caster sugar for baking structure, powdered sugar for frostings and dusting.

More Sugars & Sweeteners

Related Converters

Values are approximate and can vary depending on how the ingredient is measured. For precision baking, we recommend using a digital kitchen scale.