1 Cup Oats in Grams: Rolled, Quick, Instant & Steel-Cut
1 cup of old-fashioned rolled oats weighs 90 grams (3.17 oz). 1 cup of steel-cut oats weighs 160 grams (5.64 oz). Complete oats density guide.
Quick conversion matrix
| Measurement | Equivalent A | Equivalent B | Equivalent C |
|---|---|---|---|
| 1 Cup Old Fashioned Rolled Oats | 90.0 Grams | 3.17 Dry Ounces | Flaked Groats |
| 1 Cup Quick-Cooking Oats | 85.0 Grams | 3.00 Dry Ounces | Finely Cut Flakes |
| 1 Cup Steel-Cut Oats | 160.0 Grams | 5.64 Dry Ounces | Dense Chopped Kernels |
| 1/2 Cup Rolled Oats (Single Serving) | 45.0 Grams | 1.59 Dry Ounces | 150 Calories |
Chef & measurement rules
Rolled oats are large, light flakes (90g per cup), while steel-cut oats are dense whole kernels (160g per cup).
Never swap steel-cut oats for rolled oats in cookie recipes without par-cooking.
A standard 1/2 cup dry oatmeal breakfast serving is 45 grams (1.59 oz).
How Many Grams in 1 Cup of Oats?
1 standard level US cup of old-fashioned rolled oats weighs exactly 90 grams (3.17 ounces).
Because oats vary dramatically in physical milling, their weight per cup shifts with processing: Quick oats weigh 85g/cup, instant oats weigh 80g/cup, and dense steel-cut oats weigh a heavy 160g/cup (nearly 78% heavier per cup than rolled oats!).
For overnight oats and oatmeal cookies, weighing 90 grams per cup on a digital scale ensures consistent texture and moisture absorption.
Frequently Asked Questions
How many grams is 1 cup of rolled oats?
1 US cup of old-fashioned rolled oats weighs 90 grams (3.17 dry ounces).
How many grams in 1/2 cup of oats?
1/2 cup of rolled oats weighs 45 grams (1.59 dry ounces), the standard single-serving breakfast portion.