Sugar is one of the most weight-variable ingredients in baking. Unlike flour — where packing is the main culprit — sugar has multiple varieties with genuinely different densities, and each one has its own gram weight per cup. Granulated and caster sugar are similar in weight because they’re both dry, free-flowing crystals. Powdered sugar is the outlier: it’s been ground to a fine powder and is much lighter per cup than any other variety, which is why swapping it into a recipe by cup measure (rather than grams) can dramatically under-sugar a baked good.

Brown sugar compounds the issue further because recipes almost always specify whether it should be packed or loosely filled — and the difference is about 40 grams per cup, which is enough to noticeably affect sweetness and moisture in the finished result. If your recipe doesn’t specify, packed is the standard assumption for brown sugar in North American baking.

All weights below are for a standard US cup (240ml), filled using the spoon-and-level method unless noted. For fractional cup amounts, multiply the 1-cup gram weight by the fraction — or use the Ingredient Converter to get any amount instantly.

Sugar doesn’t have the same packing problem as flour, but measuring method still affects the final weight — especially for powdered sugar. Here’s what changes the number and by how much.

Granulated sugar is relatively forgiving. Spooning it into the cup versus scooping directly adds about 10–20g per cup — a small but real difference in a recipe calling for multiple cups. For everyday baking, spooning and levelling is accurate enough. For precision baking — patisserie, macarons, caramel work — weighing in grams eliminates the variable entirely. There’s no need to sift granulated or caster sugar before measuring.

The 40g difference between packed and loose brown sugar (220g vs 180g) is significant — it’s the equivalent of about 3 tablespoons of extra sugar, plus the additional moisture that brown sugar contributes. When a recipe says “packed”, it means press the sugar firmly into the cup with the back of a spoon until it holds its shape when turned out. If your recipe says “lightly packed”, aim for somewhere between the two. If it says nothing, default to packed.

Powdered sugar is the most measuring-sensitive sugar. It compresses easily, lumps readily, and sifted vs unsifted can differ by 10–15g per cup. Most American baking recipes assume unsifted powdered sugar measured by spooning (about 130g). British and Australian recipes more often assume sifted (120g). If you’re converting a recipe across cuisines, confirm which method the original author intended. For buttercream and glaze recipes — where powdered sugar is used in large quantities — a 15–20g discrepancy per cup multiplies quickly and can change the texture noticeably.

A quick reference for granulated white sugar — the most commonly used sugar in baking recipes. All weights use the spoon-and-level method.