Oats and Oatmeal Nutrition Facts, Dry and Cooked

Oats are a cereal grain, and every common form of plain oats is a whole grain: the hull is removed, but the bran, germ and endosperm of the kernel (the groat) stay together. The record on this page covers regular (old-fashioned) rolled oats and quick oats, measured dry and without added vitamins or minerals.

That last point matters when you compare labels. Many instant oatmeal packets are fortified with added iron and B vitamins, and flavored ones contain added sugar and salt, so their panels can look quite different from plain oats even though the grain is the same.

• Steel-cut oats: whole groats chopped into pieces. Chewy, and the slowest to cook.
• Rolled (old-fashioned) oats: groats steamed and flattened into flakes.
• Quick oats: rolled thinner or cut smaller, so they cook in a few minutes.
• Instant oats: precooked, dried and rolled very thin; often sold in flavored packets.
• Oat flour: oats ground fine for baking. See oat flour nutrition.

Per gram, plain oats in all these forms have nearly the same nutrition. Per cup they do not: steel-cut oats are dense, so packages typically list a quarter cup of steel-cut oats as a serving against half a cup of rolled oats for about the same weight. Weigh oats, or compare labels by grams, rather than by cups.

Oats absorb liquid as they cook, so half a cup of dry rolled oats becomes about a cup of oatmeal. The calories do not change, they are just spread through more weight. That is why cooked oatmeal looks low in calories per 100 g; most of that weight is water. Count oatmeal by the dry oats you started with.

Cooking oats in milk instead of water adds the milk's calories, protein, fat and sugar. Overnight oats work the same way: the oats are unchanged, and the total is the oats plus the milk, yogurt and toppings you add.

Beyond hot oatmeal and overnight oats, rolled oats go into granola, muesli, oatmeal cookies, muffins and the crumble topping on fruit crisps. They are blended into smoothies, ground into flour for pancakes, and used as a binder in meatballs and meatloaf in place of breadcrumbs. Food manufacturers use oats in breakfast cereals, granola and snack bars, baked goods, and oat-based drinks.

• Oatmeal. Oats cooked in water or milk, topped with fruit, nuts or seeds. Whole Milk · Banana · Blueberries · Walnuts
• Overnight oats. Oats soaked in milk or yogurt in the refrigerator, eaten cold. Whole Milk · Greek Yogurt · Chia Seeds
• Granola. Oats baked with honey or sugar, oil and nuts until crisp. Honey · Almonds · Coconut Oil
• Oatmeal cookies. Cookies made with oats, butter, brown sugar, flour and egg. Butter · Brown Sugar · All-Purpose Flour · Egg
• Fruit crisp. Baked fruit under a topping of oats, butter and sugar. Apple · Blueberries · Butter
• No-bake energy bites. Oats rolled with peanut butter, honey and chocolate chips. Peanut Butter · Honey · Chocolate Chips

Keep oats in an airtight container in a cool, dry pantry, where they keep for months. Because the whole grain includes the germ, with its small amount of natural fat, very old oats can taste stale; buy amounts you will use. Cooked oatmeal and overnight oats keep a few days in the refrigerator.

For granola, bars, cookies or overnight oats, weigh the dry oats that go into the recipe and use dry data like this page, then set servings from the finished product weight. Oats contain no gluten themselves, but regular oats are often contaminated with wheat or barley during growing and milling. A product labeled gluten-free must contain fewer than 20 parts per million of gluten, which in practice means using oats sourced and tested as gluten-free. Build the recipe in the label generator or the recipe nutrition calculator, and check the reference amount for your category, such as cereal or bars, in the RACC lookup.