⚖️ Comparison · Updated for 2026

Caster Sugar vs Granulated / Icing Sugar

Side-by-side comparison, when-to-use-each guide, and instant conversion. Reviewed for 2026.

Quick answer: Granulated: large crystals, standard table sugar. Caster: finer crystals, dissolves faster — UK baking default. Icing (US 'powdered'): finest, with a little anti-caking agent (often starch), used for frostings/dusting. Substituting incorrectly is the most common cause of grainy or under-risen bakes.

Use Caster Sugar when…

UK creamed cake batters, meringues, sponges, anywhere fast-dissolving sugar matters.

Use Granulated / Icing Sugar when…

Granulated: tea/coffee, savoury cooking, crystal-topped pies. Icing: frosting, dusting, royal icing.

Aspect	Caster Sugar	Granulated / Icing Sugar
Crystal size	Fine	Coarse / Powder
Best for	UK baking, meringue	Granulated: cooking. Icing: frosting
Sweetness	Same as granulated	Same / roughly 97% sugar + anti-caking agent
Substitute in pinch	Pulse granulated in blender briefly	Granulated for caster (works in most cases)

Frequently asked

Can I use granulated instead of caster sugar?

In most cake recipes, yes — but cream the butter longer to dissolve the larger crystals. In meringues, no — granulated will leave grit. In sponges, expect slightly denser texture.

What is US 'superfine sugar'?

US superfine sugar = UK caster sugar. Same product, different names. The US 'baker's sugar' label also matches UK caster.

Reviewed for 2026. This comparison is general guidance based on publicly available information. Prices, rates, rules and specifications change, so check current details with the provider or an official source before making a decision. Built by a UK-based qualified primary teacher and FA Level 2 coach as part of 247QuickTools' free utility-tools project. We don't sell SEO links or accept paid placements in this content.

Frequently asked questions

Can I use granulated instead of caster sugar?

In most cake recipes, yes — but cream the butter longer to dissolve the larger crystals. In meringues, no — granulated will leave grit. In sponges, expect slightly denser texture.

What is US 'superfine sugar'?

US superfine sugar = UK caster sugar. Same product, different names. The US 'baker's sugar' label also matches UK caster.