1 Cup Oats in Grams: Rolled, Quick and Steel Cut Oats Chart

Oats are flattened, cut or ground in different ways, and each shape packs into a cup differently. Flakes leave lots of air between them, so rolled oats are light. Steel cut pieces are small and dense, so a cup weighs much more.

1 Cup Rolled Oats in Grams

1 cup rolled oats in grams is 89 grams, using the King Arthur value this site uses for every oat chart. Rolled oats and old fashioned oats are the same thing. King Arthur’s own brand of rolled oats weighs more, at 113 grams per cup.

Why Sources Give Different Numbers

The gap between 80, 81 and 89 grams comes from how the cup is filled. A cup that is scooped and shaken holds more oats than one that is spooned in loosely. For baking, weigh the oats or use the 89 gram value for every cup.

This chart covers the cup sizes found in cookie, granola and overnight oat recipes. The first column is the value used across this site. The other columns show USDA dry oats, steel cut oats and oat flour.

1/2 Cup and 1/3 Cup of Oats in Grams

Half a cup of rolled oats weighs 45 grams. A third of a cup weighs 30 grams, and a quarter cup weighs 22 grams. Two cups weigh 178 grams.

Divide the grams by 89 to get cups of rolled or quick oats. Divide by 5.6 to get tablespoons instead. The last column gives the closest cups and spoons to scoop.

40g Oats in Cups

40g oats in cups is 0.45 cup, or 1/3 cup plus 2 tablespoons. The Quaker Old Fashioned label calls 40 grams a 1/2 cup serving, so label cups run a little lighter than baking charts. If you have no scale, a level 1/2 cup is close enough for porridge.

What 40 Grams of Oats Looks Like

40 grams of oats is about 7 level tablespoons. It fills a little less than half of a standard measuring cup. That amount is 150 calories on the Quaker label.

50g, 100g and 200g of Oats in Cups

50 grams of oats is 0.56 cup, or 1/2 cup plus 1 tablespoon. 100 grams is 1.12 cups, or 1 cup plus 2 tablespoons. 200 grams is 2 1/4 cups.

Oats soak up water as they cook, so a cup of cooked oatmeal weighs far more than a cup of dry oats. USDA data lists 234 grams for 1 cup of oatmeal made with water. That is more than 2 1/2 times the weight of a cup of dry rolled oats.

Steel Cut Oats Water Ratio

Quaker cooks 1/4 cup of steel cut oats in 1 1/2 cups of water or milk for one serving. For four servings, it uses 1 cup of oats and 4 cups of liquid. One cup of dry steel cut oats weighs about 140 grams.

You only need one number for each type of oat. Use 89 grams per cup for rolled and quick oats. Use 140 grams per cup for steel cut oats.

Cups to Grams

Multiply the cups by the grams per cup. For 3/4 cup of rolled oats, 0.75 × 89 = 67 grams. For 1/2 cup of steel cut oats, 0.5 × 140 = 70 grams.

Grams to Cups

Divide the grams by the grams per cup. For 60 grams of rolled oats, 60 ÷ 89 = 0.67 cup, which is 2/3 cup. For 150 grams, 150 ÷ 89 = 1.69 cups, or about 1 2/3 cups.

Tips for Measuring Oats

Oats are light and loose, so the way you fill the cup matters. These habits keep your cups close to the chart. They matter most in cookies and granola bars.

• Spoon and level. Spoon the oats into the cup, then sweep the top flat.
• Do not shake or pack. Shaking settles the flakes and adds more weight.
• Match the oat type. Swap rolled and quick oats freely, but not steel cut oats.
• Weigh for baking. A scale removes the gap between 80 and 89 grams per cup.
• Check the label serving. The FDA reference amount for dry hot cereal is 40 grams, which is why oat labels use it.