Oat Flour: Grams to Cups Conversion & How to Make Your Own

Convert oat flour between grams and cups, plus learn how to make homemade oat flour in a blender.

Oat flour is a popular gluten-free alternative (when using certified GF oats) that you can make at home. Here's everything you need to know about measuring and converting it.

Oat Flour Conversion

1 cup of oat flour = 92 grams

Amount — Grams — Cups

¼ cup — 23g — 0.25

½ cup — 46g — 0.50

1 cup — 92g — 1.00

150g — — — 1⅔ cups

200g — — — 2⅙ cups

250g — — — 2¾ cups

How to Make Oat Flour at Home

Add rolled oats or quick oats to a blender or food processor

Blend on high for 30-60 seconds until fine and powdery

Sift to remove any large pieces

Re-blend the large pieces

Conversion: 1¼ cups of whole rolled oats ≈ 1 cup of oat flour

Oat Flour vs Rolled Oats

Don't confuse them — they have different densities:

Oat flour: 92g per cup (finely ground)

Rolled oats: 90g per cup (flakes, with more air)

Substituting Oat Flour for All-Purpose Flour

Replace by weight, not volume. If a recipe calls for 125g AP flour, use 125g oat flour. By volume, you'd use about 1⅓ cups of oat flour instead of 1 cup of AP flour.

Note: Oat flour lacks gluten, so baked goods may be denser. Add ½ tsp xanthan gum per cup for better structure.

Next, read Gluten-Free Flour Conversions.