Why does a cup of flour have a different weight than a cup of sugar?

Different ingredients have different densities. Granulated sugar packs more closely than flour, so a cup of sugar (200 g) weighs about 80 g more than a cup of flour (120 g). The volume is identical; the weight isn't.

Is one US cup the same as a UK or Australian cup?

Almost — the US legal cup is 240 mL; the customary cup (used in most US cookbooks) is 236.5882365 mL. UK and Australian metric cups are 250 mL. The calculator uses the US customary cup by default, matching how most US recipes specify.

Does the calculator account for packed vs sifted flour?

The default flour density (120 g/cup) assumes 'spooned and leveled' — scoop flour into the cup with a spoon, then level with a knife. Sifted flour weighs about 110 g/cup; scooped-from-the-bag flour can reach 150 g/cup. When precision matters, weigh.

Where do these densities come from?

USDA FoodData Central, King Arthur Baking's ingredient weight chart, and BBC Good Food. Where sources disagreed slightly we used the most widely cited convention. Recipe author choices can shift these by ±10%.

Is butter weighed before or after melting?

Both work — butter's density barely changes when melted (about 5% lower). The 227 g/cup figure here is solid butter at refrigerator temperature, which matches what most recipes mean.

Eggs are typically counted, not measured by volume. If you need egg weights: 1 large egg is approximately 50 g (out of shell), 1 large yolk is 18 g, 1 large white is 30 g.

Can I add a custom ingredient?

Not in this version. The lookup table covers the 36 most common baking and cooking ingredients; a custom-density input is on the roadmap.

Are these densities accurate enough for baking?

Yes for everyday baking — within ±5% which is well inside the tolerance recipes can absorb. For laboratory-grade pastry (souffles, macarons, perfect sourdough hydration) always weigh on a scale.

Cup to Grams Converter — All Common Cooking Ingredients

Pick the ingredient, type the cups — get grams. Per-ingredient density, US measure standards.

Cooking is the one place where the same volume can mean very different weights — a cup of feathers weighs a fraction of a cup of honey. The converter below uses a per-ingredient density lookup so 1 cup of flour gives you 120 g (the King Arthur Baking standard), 1 cup of sugar gives 200 g, and 1 cup of butter gives 227 g. Thirty-six common ingredients shipped; more on request.

Ingredient

Spooned and leveled, not packed.

Volume

Unit

Grams
120.0 g
Ounces
4.23 oz
Pounds
0.2646 lb

Density for all-purpose flour: 120 gper US cup. Real-world densities vary by 5–15% depending on how an ingredient is packed (sifted vs scooped flour, packed vs loose brown sugar). When precision matters, weigh — don’t measure.

How to use

Pick the ingredient
All-purpose flour is the default. The dropdown groups the most common baking ingredients first, then lists the rest alphabetically.
Pick the direction and unit
Volume-to-weight gives you grams (the form most modern recipes use). Weight-to-volume goes the other way — useful when a recipe is in grams and your measuring cups are out.
Read all three forms
Grams is the headline; the calculator also surfaces ounces and pounds for US scale users. For volume conversions you get cups, tablespoons, teaspoons, and milliliters at once.

Common ingredients at a glance

Ingredient	1 cup (US)	1 tbsp	1 tsp
All-purpose flour	120 g	7.5 g	2.5 g
Granulated sugar	200 g	12.5 g	4.2 g
Brown sugar (packed)	213 g	13.3 g	4.4 g
Butter	227 g	14.2 g	4.7 g
Olive oil	216 g	13.5 g	4.5 g
Honey	340 g	21.3 g	7.1 g
Milk (whole)	244 g	15.3 g	5.1 g
Cocoa powder	85 g	5.3 g	1.8 g
Rolled oats	81 g	5.1 g	1.7 g

Frequently asked questions

Why does a cup of flour have a different weight than a cup of sugar?: Different ingredients have different densities. Granulated sugar packs more closely than flour, so a cup of sugar (200 g) weighs about 80 g more than a cup of flour (120 g). The volume is identical; the weight isn't.
Is one US cup the same as a UK or Australian cup?: Almost — the US legal cup is 240 mL; the customary cup (used in most US cookbooks) is 236.5882365 mL. UK and Australian metric cups are 250 mL. The calculator uses the US customary cup by default, matching how most US recipes specify.
Does the calculator account for packed vs sifted flour?: The default flour density (120 g/cup) assumes 'spooned and leveled' — scoop flour into the cup with a spoon, then level with a knife. Sifted flour weighs about 110 g/cup; scooped-from-the-bag flour can reach 150 g/cup. When precision matters, weigh.
Where do these densities come from?: USDA FoodData Central, King Arthur Baking's ingredient weight chart, and BBC Good Food. Where sources disagreed slightly we used the most widely cited convention. Recipe author choices can shift these by ±10%.
Is butter weighed before or after melting?: Both work — butter's density barely changes when melted (about 5% lower). The 227 g/cup figure here is solid butter at refrigerator temperature, which matches what most recipes mean.
Why no eggs?: Eggs are typically counted, not measured by volume. If you need egg weights: 1 large egg is approximately 50 g (out of shell), 1 large yolk is 18 g, 1 large white is 30 g.
Can I add a custom ingredient?: Not in this version. The lookup table covers the 36 most common baking and cooking ingredients; a custom-density input is on the roadmap.
Are these densities accurate enough for baking?: Yes for everyday baking — within ±5% which is well inside the tolerance recipes can absorb. For laboratory-grade pastry (souffles, macarons, perfect sourdough hydration) always weigh on a scale.

About

Why pro recipes use grams

Volume is unreliable for compressible ingredients (flour can pack 25% denser than its un-tapped state) and for ingredients you scoop differently (cocoa powder, brown sugar). Weight removes that variable entirely — 100 g of flour is 100 g of flour, no matter who measured it. King Arthur, Christina Tosi, and Stella Parks all publish in grams for this reason.

When volume is fine

Liquids (water, milk, oil) have stable densities and pour reliably into a measuring cup. For these, cups are as good as grams. Solids that resist packing (whole eggs, fruit pieces, chocolate chips) are usually fine too. Anything fluffy, sticky, or sift-able benefits from being weighed.