How many grams in a cup of molasses?

1 cup of molasses weighs 337 g by USDA. King Arthur Baking lists 85 g per quarter cup, which is 340 g per cup.

Sources: USDA FoodData Central, King Arthur Baking ingredient weight chart · Checked October 22, 2026

Amount

Unit

337 g 11.9 oz

Sources range from 337 g to 340 g for 1 cup.

Converting a whole recipe?

Sous Chef converts every ingredient in a recipe to grams and millilitres in one tap, rounded to amounts you would actually weigh.

Molasses cups to grams table

Using 337 g per US cup. A US cup is 236.6 mL; 1 cup is 16 tablespoons.

Molasses cups to grams
US cups	Grams	Ounces	Tablespoons
⅛ cup	42 g	1.5 oz	2
¼ cup	84 g	3 oz	4
⅓ cup	112 g	4 oz	5.3
½ cup	169 g	5.9 oz	8
⅔ cup	225 g	7.9 oz	10.7
¾ cup	253 g	8.9 oz	12
1 cup	337 g	11.9 oz	16
1½ cups	506 g	17.8 oz	24
2 cups	674 g	23.8 oz	32
3 cups	1,011 g	35.7 oz	48
4 cups	1,348 g	47.5 oz	64

Why sources disagree

Molasses is dense and thick, so a cup weighs over 40% more than a cup of water. The two sources agree within 3 g. It clings to the cup, so weighing it straight into the bowl is more accurate than scraping out a measuring cup.

Source	Listed as	Grams per cup
USDA FoodData Central Molasses	1 cup = 337 g	337 g
King Arthur Baking ingredient weight chart Molasses	¼ cup = 85 g	340 g

Bold row is the figure the calculator uses. Figures listed for a smaller measure are multiplied up to one cup.

How to measure molasses accurately

Spray the cup or spoon lightly with oil, or weigh the molasses into the bowl, so it does not stick.
Weigh on a digital scale when you can, since it skips the mess of measuring cups.
Use a clear liquid measuring cup on a flat counter and read it at eye level.

Convert the whole recipe, not one line

Converting a recipe one ingredient at a time is where mistakes slip in. Sous Chef imports a recipe from a link or pasted text, then converts every ingredient at once: dry ingredients and butter to grams, liquids to millilitres. Tap again to go back to cups.

US recipe

2¼ cups all-purpose flour
1 cup butter, softened
¾ cup brown sugar, packed
1½ cups milk

In Sous Chef, after "Convert to metric"

275 g all-purpose flour
225 g butter, softened
170 g brown sugar, packed
350 ml milk

Example output. Sous Chef rounds to amounts you would actually weigh, so its numbers can differ by a few grams from the table above.

Common questions

How many grams is half a cup of molasses?

Half a cup of molasses is about 168.5 g, using 337 g per cup.

How many grams is 1 tablespoon of molasses?

1 tablespoon of molasses is about 21 g, since 337 g per cup divided by 16 is 21 g. USDA's own tablespoon serving is listed at 20 g.

More conversions

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