Cup & Gram

Grams of Oats to Cups

One US cup of rolled oats weighs 89 grams. To convert grams of rolled oats to cups, divide the grams by 89 — so 100 g is 1 ⅛ cups and 89 g is exactly 1 cup.

250 g Rolled oats (old-fashioned) = 2 ¾ cups

Exactly 2.81 cups — or measure 2 cups + 13 tbsp.

Oats cups-to-grams chart

US cups of rolled oats to grams (89 g per cup)
CupsGramsOunces
¼ cups 22 g 0.8 oz
⅓ cups 30 g 1.1 oz
½ cups 45 g 1.6 oz
⅔ cups 59 g 2.1 oz
¾ cups 67 g 2.4 oz
1 cup 89 g 3.1 oz
1½ cups 134 g 4.7 oz
2 cups 178 g 6.3 oz

How to measure rolled oats

Rolled oats are light and irregular — a level cup is only about 89 g. Scoop-and-level is fine; the flakes don’t compact much. Quick oats weigh nearly the same, but steel-cut oats are much denser and don’t substitute by volume.

Grams of oats to cups — every amount

Other ingredients

Density 89 g/cup — sources: King Arthur Baking ingredient weight chart, Quaker nutrition label, USDA FoodData Central. Data verified 2026-08-20. Methodology.