How many grams is 1 cup of rolled oats?

One US cup (240 ml) of rolled (old-fashioned) oats weighs approximately 90 grams. Because rolled oats are flat and irregular, they pack loosely and weigh significantly less per cup than steel-cut oats.

How many grams is 1 cup of quick oats?

One US cup of quick-cooking oats weighs approximately 89 grams — nearly the same as rolled oats because the thinner flakes pack to a similar density.

How many grams is 1 cup of steel-cut oats?

One US cup of steel-cut oats weighs approximately 160 grams. Steel-cut oats are dense, small pieces that pack tightly, so they are much heavier per cup than rolled or quick oats.

How many grams is 1 cup of oat flour?

One US cup of oat flour weighs approximately 120 grams when spooned and leveled. Sifted oat flour weighs slightly less, and scooped oat flour can weigh up to 140 grams, so weighing is always the most accurate method.

What is the difference between a US cup and a metric cup?

A US culinary cup is commonly treated as 240 ml, while an international metric cup equals 250 ml. The 10 ml difference is small but adds up in larger quantities. Most American recipes use the US cup; Australian and some European recipes use the 250 ml metric cup.

Can I substitute oat flour for rolled oats by weight?

Not directly. Oat flour is finely ground and behaves like a flour, while rolled oats retain their flake texture. They are not interchangeable in most recipes. Always use the oat form the recipe specifies and weigh each separately.

Oats Cups to Grams Converter

Enter a volume of oats in cups, choose the oat type and cup size, and instantly see the weight in grams and ounces.

Convert to Grams

Amount

Unit

Oat type

Cup standard

Density Reference

Grams per US cup (240 ml) for each oat type.

Oat Type	g / cup	oz / cup
Rolled oats	90 g	3.17 oz
Quick oats	89 g	3.14 oz
Steel-cut oats	160 g	5.64 oz
Oat flour	120 g	4.23 oz

Unit equivalents (1 US cup)

Unit	Fraction of cup	ml
1 cup	1	240 ml
1 tablespoon	1/16	15 ml
1 teaspoon	1/48	5 ml

Quick-Reference Table

Pre-calculated gram weights for common cup amounts. Showing US cups.

Amount	Grams	Ounces

Summary

Oats come in four common forms — rolled (old-fashioned), quick-cooking, steel-cut, and oat flour — each with a different weight per cup due to varying particle sizes and packing density. Rolled oats weigh about 90 grams per cup, quick oats around 89 grams, steel-cut oats roughly 160 grams, and oat flour approximately 120 grams. This converter lets you select your oat type, enter the amount in cups (US 240 ml or metric 250 ml), and get the precise weight in grams and ounces for accurate baking and cooking.

How it works

Enter the number of cups you want to convert.
Select the unit: cups, tablespoons, or teaspoons.
Choose your oat type: rolled oats, quick oats, steel-cut oats, or oat flour.
Select the cup standard: US cup (240 ml) or metric cup (250 ml).
The result in grams and ounces appears instantly.
Scroll down to the quick-reference table for common pre-calculated amounts.

Use cases

Weigh oats precisely on a kitchen scale instead of measuring by cup.
Convert an American oatmeal recipe to metric weights for accuracy.
Scale a granola or energy-bar recipe up or down to any batch size.
Ensure consistent results when making overnight oats or oatmeal cookies.
Convert oat flour in baking recipes that list volume measurements.
Calculate nutrition information that requires exact gram weights.
Compare the actual density difference between steel-cut and rolled oats.
Teach beginner bakers how different oat forms vary significantly in weight.

Frequently Asked Questions

Last updated: 2026-05-29 · Reviewed by Nham Vu