Converter
Why molasses needs its own conversion
Molasses weighs about 340g per cup — notably dense — closer to syrups than most dry ingredients. King Arthur = 340 g/cup (1/4 cup = 85 g); USDA FoodData Central = ~337 g. Very close agreement. A cup is a unit of volume, so ingredients this different in density can't share one generic conversion factor — using a single "1 cup = X g" rule for everything will be wrong for at least some of what you cook.
Common measurement mistakes
- Using a generic cup-to-gram factor for every ingredient — molasses does not weigh the same per cup as most other ingredients.
- Measurement note: King Arthur = 340 g/cup (1/4 cup = 85 g); USDA FoodData Central = ~337 g. Very close agreement.
- Confusing weight ounces with fluid ounces when a recipe lists "oz" — they are not interchangeable.
Frequently asked questions
How many grams are in a cup of molasses?
About 340g, king Arthur = 340 g/cup (1/4 cup = 85 g); USDA FoodData Central = ~337 g. Very close agreement.
Does this conversion work for every brand or variety of molasses?
It’s a close approximation based on King Arthur Baking. Minor variations in moisture, grain, or brand can shift the exact weight slightly, but this figure works well for everyday cooking and baking.