Grams or cups — for the ingredient you actually have.

Most volume-to-weight conversions you find online quietly assume a single density — often that of water, which is approximately right for thin liquids and approximately wrong for everything else. A cup of all-purpose flour, packed by a recipe writer in a humid Brooklyn kitchen, isn't the same weight as a cup of the same flour, sifted, in a dry alpine cabin. But the order-of-magnitude differences between ingredients — flour, sugar, oil, honey — dwarf those packing variations, and that's what this converter is calibrated against.

Where the densities come from

We use a single reference table of grams-per-US-cup, drawn primarily from King Arthur Baking's ingredient weight chart (the most rigorously tested baking-ingredient density list publicly available) and the USDA FoodData Central database for non-baking ingredients. Where the two sources disagree, we use King Arthur for baking ingredients and USDA for produce, dairy, and general pantry items. All values assume:

• 1 US cup = 236.588 ml (the standard US legal cup, not the 240 ml “nutritional” cup).
• Flour is spooned and levelled, not scooped.
• Brown sugar is packed, the convention every American recipe assumes unless stated otherwise.
• Salts vary wildly by brand because of crystal size; we list the most common varieties separately.

The most common conversions

• 1 cup all-purpose flour = 120 g
• 1 cup bread flour = 127 g
• 1 cup cake flour = 114 g
• 1 cup whole-wheat flour = 113 g
• 1 cup granulated sugar = 200 g
• 1 cup packed brown sugar = 213 g
• 1 cup confectioners' sugar = 113 g
• 1 cup butter = 227 g (1 stick = 113 g)
• 1 cup honey = 340 g
• 1 cup milk = 245 g
• 1 cup water = 237 g

The salt problem

Of all the ingredients people convert wrong, salt is the worst. By volume, different salts vary enormously because of their crystal shape:

• Table salt: ≈ 292 g per cup (small, dense crystals)
• Diamond Crystal kosher salt: ≈ 142 g per cup (big, flaky pyramids)
• Morton kosher salt: ≈ 240 g per cup (denser flakes)

That means 1 tablespoon of Diamond Crystal weighs about half as much as 1 tablespoon of table salt. If a recipe calls for a tablespoon of table salt and you swap in Diamond Crystal volume-for-volume, you've under-salted by about 50%. Always convert salt by weight — and when a recipe calls for “kosher salt” without specifying a brand, assume Diamond Crystal (the American professional default) unless you're cooking from a Morton-leaning source like America's Test Kitchen.

When density assumptions break down

Reference densities work for the average bag of an ingredient, but real life produces edge cases. A few worth knowing:

• Flour absorbs moisture from the air. A bag stored in a humid kitchen will weigh more per cup than the same bag stored airtight in a dry pantry.
• Brown sugar dries out. An old bag has lost moisture; the same packed cup will weigh measurably less than a fresh one.
• Butter softness affects packed measurement. Softened butter packs into a measuring cup more densely than cold cubes.
• Cocoa absorbs moisture, too. Dutch-process cocoa varies more by brand than within itself; we list a midpoint.

The fix for all of these is the same: weigh, don't measure, when the recipe is sensitive enough to care.

Pairing with the scaler

If you're scaling a recipe and want to switch from volume to weight at the same time, the workflow is: open the scaler, scale the ingredients to your target servings, then run any volume measurements you want to switch to weights through this converter, ingredient by ingredient. Or if you trust the source recipe to weigh up well, switch first with this converter and scale later with the weight converter.