Rolled Oats: Cups to Grams

1 US cup of rolled oats weighs about 90 grams.

Three quarters of a US cup of rolled oats is about 67.5 grams (12 tablespoons).

2/3 of a US cup of rolled oats is about 60 grams.

Half a US cup of rolled oats is about 45 grams — half of the 90 g in a full cup.

A third of a US cup of rolled oats is about 30 grams.

A quarter US cup of rolled oats is about 22.5 grams (4 tablespoons).

1 tablespoon of rolled oats is about 5.6 grams (a cup is 16 tablespoons).

1 1/4 US cups of rolled oats weigh about 112.5 grams.

1 1/2 US cups of rolled oats weigh about 135 grams — one full cup (90 g) plus half a cup (45 g).

2 US cups of rolled oats weigh about 180 grams.

100 grams of rolled oats is about 1.11 cups.

250 grams of rolled oats is about 2.78 cups (at 90 g per cup).

500 grams of rolled oats is about 5.56 cups.

About 90 grams for old-fashioned rolled or quick oats measured in a US cup — the value this page uses. Published figures honestly spread from 80 to 98 g per cup (Quaker's label works out to 80 g, USDA lists 81 g, King Arthur 89 g, Bob's Red Mill 98 g), so any value in that band is defensible. Steel-cut oats are a different story at about 160 g per cup, and a 250 mL metric cup of rolled oats holds about 95 g.

About 48 grams. New Zealand (and Australian) recipes use the 250 mL metric cup, so a full metric cup of rolled oats is about 95 g and half a metric cup about 48 g. The "wholegrain" or "wholemeal" oats on NZ packs like Harraways are ordinary wholegrain rolled oats — all rolled oats keep the bran and germ — so they weigh the same. Using a US half cup instead? That's about 45 g.

Yes — use the same chart for both. King Arthur's ingredient chart lists old-fashioned and quick-cooking oats as a single entry (89 g per cup), and Quaker's labels give both the identical 40 g per half-cup serving. Quick oats are just rolled oats cut smaller and rolled thinner, which changes cooking time and baked texture, not weight per cup. Instant oatmeal is sold in packets instead — typically 28 g each.

They're UK names on the same family tree. Jumbo oats are thick flakes rolled from the whole groat — the match for US old-fashioned or thick-rolled oats, and the thick flakes run heavier (King Arthur's own thick-rolled oats weigh 113 g per cup). Porridge oats are the standard smaller UK flake, rolled from cut groats — use the regular ~90 g chart. Pinhead oatmeal is steel-cut oats (about 160 g per cup), and Scottish oatmeal is stone-ground, not flaked.

About 234 grams per US cup (USDA, cooked with water) — much more than the 90 g of a cup of dry oats, because oatmeal is mostly absorbed water. One cup of dry rolled oats (90 g) cooks up to roughly 2 cups of porridge. When a US baking recipe calls for "1 cup oatmeal" in cookies or crumble, it means dry rolled oats, not cooked porridge.

About 68.5 g of rolled oats. The cup that comes with a rice cooker is a Japanese go of 180 mL — three-quarters of a US cup (236.6 mL) — so it holds three-quarters of this page's 90 g: 68.5 g, or 61.6 g by USDA's lighter 81 g cup, and about 121.7 g of steel-cut oats. Quaker's 1/2-cup (40 g) serving is 0.66 of a rice cup, so a level rice cup of Quaker oats is a generous serving and a half. Don't use the cooker's rice lines for the water, though — a rice cup of white rice weighs 140.8 g, twice the oats, and oats want roughly twice their volume in water.

About 38 g per 100 mL for rolled oats, or 0.38 g/mL (90 g ÷ 236.6 mL). USDA's measured cup gives 0.34 g/mL (34 g per 100 mL) and Bob's Red Mill's label works out to 0.41, so any 100 mL of flakes is 34–41 g. Steel-cut oats are nearly twice as dense at 0.68 g/mL (68 g per 100 mL), and cooked oatmeal is 0.99 g/mL — essentially water.

About 4 serves. One and a third cups of dry rolled oats is 120 g, and an Australian or New Zealand standard serve of grain food works out to about 30 g of dry oats (the guideline's own examples are 1/2 cup / 120 g of cooked porridge or 1/4 cup / 30 g of muesli, each about 500 kJ), so 120 ÷ 30 = 4.0. In US terms it is 4.2 ounce-equivalents (1 oz of dry oats each), and under the Whole Grains Council's 16 g rule it is 7.5 whole-grain servings. That is a lot of oats: 1 1/3 cups dry cooks up to about 2.74 cups of porridge, two to three breakfasts.

All of it — about 45 g of whole grain in a half cup (45 g) of rolled oats, because oats are 100% whole grain: the flake is the entire groat, bran and germ included. Labels print "40 g of whole grain per serving" because the serving Quaker weighs is 1/2 cup = 40 g; use 40 g if you measure like the label, 45 g if you level a US cup the way this chart assumes. Either way that is 2.5–2.8 Whole Grains Council servings (16 g each), or about 1.6 US ounce-equivalents.

About 43.7 g, or a rounded half cup of dry rolled oats. USDA weighs a cup of oatmeal cooked with water at 234 g, and oats gain about 5.35× their weight in the pot (Quaker's 1/2 cup oats + 1 cup water cooks down to close to a cup), so the dry equivalent is 234 ÷ 5.35. Cooked grains are not interchangeable by dry weight: a cup of cooked white rice comes from about 56.4 g of dry rice because rice only gains 2.8×. The <a href="/dry-to-cooked/">dry-to-cooked converter</a> has the factor for every grain.

Half a US cup exactly on this page's 90 g figure (45 ÷ 90 = 0.5). By Quaker's label (40 g per 1/2 cup) 45 g is a slightly heaped half cup, and by Bob's Red Mill's (49 g) a slightly short one, so "half a cup" is the right answer for any brand — it is also exactly what Bob's Red Mill prints for a half-cup serving of its quick oats, and one and a half Australian standard serves.

1 1/2 cups is 135 g and 2 1/2 cups is 225 g of old-fashioned or quick oats — multiply 90 g by the number of cups (2 cups = 180 g, 3 cups = 270 g). Measured with Quaker's 40 g half-cup those would read 120 g and 200 g, so for a big batch of granola or an oat bake the cup matters more than for a bowl of porridge: a 10% cup-to-cup difference on 2 1/2 cups is 22.5 g, a full quarter cup of oats.

49 g by the label on Bob's Red Mill Old Fashioned Rolled Oats (a 1/2-cup serving), 45 g for its quick-cooking oats and 50 g for its extra thick rolled oats — against 45 g for a half cup on this chart and 40 g on Quaker's label. Bob's larger, thicker flakes settle heavier in the cup, so if a recipe was written with Bob's in mind and you scoop, expect the heavy end of the 80–100 g-per-cup range; weighing removes the question.

About 341 kcal in a level US cup (90 g), using USDA's 379 kcal per 100 g for dry rolled or quick oats, with 11.8 g of protein, 5.9 g of fat and 9.1 g of fiber. Half a cup is about 171 kcal — Quaker's label puts its 40 g half-cup at 150 kcal, the same 375 kcal per 100 g — and a cup of cooked oatmeal (234 g, USDA) is only about 166 kcal, because most of it is water.