One US cup of rolled oats weighs about 90 grams. That single number is what makes this conversion possible, and it is why baking by weight is more reliable than baking by volume.
Very light for its volume because of all the trapped air. Volume measures depend on how the ingredient is packed into the cup, while a gram is a gram no matter how you scoop it.
Enter your amount above to convert it. The table below covers the fractions recipes actually call for, including thirds and eighths of a cup.
The rolled Oats gram to cup table below carries 11 pre-computed rows, from 25 g to 1000 g, so a figure can be checked against this page without typing anything into it. It loads pre-filled, with grams of rolled oats at 90 g, and the answer updates on every keystroke after that. Every symbol in the formula — 3 of them (cups, 90, grams) — is defined above rather than left as notation to decode. Most visitors arrive here from, or leave for, Cocoa Powder: Cups to Grams Converter and Rolled Oats: Cups to Grams Converter.
The formula
cups- Volume of rolled oats in US cups
90- Grams in one US cup of rolled oats
grams- Weight of the ingredient
How it works, step by step
- Enter your quantity of rolled oats.
- The tool applies the density of 90 g per US cup.
- The converted figure appears immediately, along with an ounce equivalent.
- Use the table for common recipe fractions without typing anything.
Worked examples
A standard single batch
If a recipe lists 180 g of rolled oats, that is 2 cups. Weighing is faster than levelling two separate cups.
Scaling a recipe by half
45 g of rolled oats is half a cup, which is the amount most often halved when scaling a recipe down.
Checking the 150 g row
The reference table lists Grams = 150 g, giving Cups: 1.67 cups, Ounces: 5.3 oz. Entering that above should reproduce the same figures — if it does not, the input is being read differently to the way the table assumes.
Frequently asked questions
How many grams are in a cup of rolled oats?
About 90 grams for a US cup. Very light for its volume because of all the trapped air.
How many grams are in a tablespoon of rolled oats?
A US tablespoon is one sixteenth of a cup, so about 5.6 grams.
Why do different sources give different gram values?
Because volume measuring is genuinely imprecise. How you fill the cup changes the weight, sometimes by 20% or more for flours and powders. Published values assume a specific method — usually spooned and levelled — and this page uses that convention.
Should I bake by weight or volume?
By weight whenever a scale is available. It is more repeatable, faster with fewer dishes, and it is the reason professional recipes are written in grams.
How precise is the volume in cups?
Internally the maths runs at full double precision and the display keeps the significant figures that carry information, dropping the digits that are only rounding noise. Rounding happens at the display step alone, so nothing accumulates error as you change the input. The figure is reported in cups.
What formula does the Rolled Oats: Grams to Cups Converter use?
It computes cups = grams ÷ 90, where cups is volume of rolled oats in US cups; 90 is grams in one US cup of rolled oats; grams is weight of the ingredient. The same expression is printed on the page above the inputs, so the result can be reproduced by hand or in a spreadsheet.
Rolled Oats conversion table
| Grams | Cups | Ounces |
|---|---|---|
| 25 g | 0.28 cups | 0.9 oz |
| 50 g | 0.56 cups | 1.8 oz |
| 75 g | 0.83 cups | 2.6 oz |
| 100 g | 1.11 cups | 3.5 oz |
| 125 g | 1.39 cups | 4.4 oz |
| 150 g | 1.67 cups | 5.3 oz |
| 200 g | 2.22 cups | 7.1 oz |
| 250 g | 2.78 cups | 8.8 oz |
| 300 g | 3.33 cups | 10.6 oz |
| 500 g | 5.56 cups | 17.6 oz |
| 1000 g | 11.11 cups | 35.3 oz |
Based on 1 US cup of rolled oats = 90 g. Very light for its volume because of all the trapped air.