Oats Grams to Cups Converter
100g of dry old-fashioned oats is about 1.12 US cups, using our 89g-per-cup reference.
Enter another weight below. Check your recipe or package too: oat cup weights can differ between references and products.
Reference: King Arthur Baking's ingredient chart lists its generic old-fashioned or quick-cooking oats entry at 89g per cup. We adopt that weight for this site's US Customary setting. The calculator is not a cooked-oatmeal converter.
Oats grams to cups
These estimates use 89g of dry oats per US Customary cup. Answers are rounded to a maximum of two decimal places.
| Dry oat weight | Approximate US cups |
|---|---|
| 25g | 0.28 |
| 40g | 0.45 |
| 50g | 0.56 |
| 75g | 0.84 |
| 89g | 1 |
| 100g | 1.12 |
| 125g | 1.4 |
| 150g | 1.69 |
| 175g | 1.97 |
| 200g | 2.25 |
| 225g | 2.53 |
| 250g | 2.81 |
| 300g | 3.37 |
| 350g | 3.93 |
| 400g | 4.49 |
| 500g | 5.62 |
| 1,000g | 11.24 |
For a reference covering several ingredients, see the printable conversion chart.
Why do some oat references use a different cup weight?
A published cup weight is a reference for a particular product or measuring convention, not a guarantee for every bag of oats.
For example, Quaker's Oats 101 guide describes 40g of raw oats as about ½ cup. Doubling that equivalent gives about 80g per cup. King Arthur's chart also has a separately named King Arthur Rolled Oats entry at 113g per cup, distinct from the generic 89g entry used here.
If your recipe provides a gram equivalent, use it. If you are working from your product's own cup-and-weight instructions, keep that reference throughout. Do not average different references or assume our calculator has automatically selected your brand.
Which oats does this converter cover?
The default is dry old-fashioned rolled oats. Its selected source entry also covers quick-cooking oats, but that shared weight reference does not make the two interchangeable in every recipe.
Quaker's guide distinguishes rolled, cut and more finely processed oat products. Their shape and cooking behavior differ. Do not extend this calculator's default to steel-cut oats, oat flour, oat bran or flavored instant-oatmeal packets without a matching reference.
If a recipe calls for a particular oat type, choose that type before converting the amount.
How to measure dry oats
If the recipe gives grams and you have a kitchen scale, set an empty bowl on it, zero the display and add the requested weight.
For a cup measurement, fill a dry measuring cup with loose oats and level the top. Avoid crushing or pressing the flakes down to fit extra into the cup. Follow any more specific measuring directions supplied with your recipe.
Keep “dry” and “prepared” amounts separate. For overnight oats, measure the dry oats before adding the other ingredients; the weight of the finished mixture includes those additions.
How the conversion works
For this page's US Customary reference:
Cups of dry oats = grams ÷ 89
For example, 50 ÷ 89 = about 0.56 cups. A decimal answer of 0.56 is a little more than half a cup, not exactly ½ cup.
For the reverse calculation, multiply cups by 89. That gives 44.5g for ½ cup under this reference. Use the calculator's direction switch or the cups-to-grams converter with dry oats selected.
Can I use these numbers for cooked oatmeal?
No. Cooked oatmeal contains added liquid, so its weight depends on the preparation. The dry-oat reference cannot tell you how many cups a finished bowl will occupy or what that bowl will weigh.
Use the dry ingredient amount when following a recipe that lists uncooked oats. For an already prepared portion, use a reference that matches the finished food and preparation instead.
What if I use a metric cup?
This table stays on the US Customary setting. Select Metric in the calculator for a 250mL cup. Scaling our baseline by volume gives about 94g per metric cup; that is a calculated estimate, not a separate source measurement.
See the cup-size guide to choose the right setting. Our grams-per-cup chart and methodology explain the reference choices and calculation rules.