The Overnight Oats Ratio, in Grams
The overnight oats ratio is 50g rolled oats to 150ml milk, plus 1 tbsp chia seeds. In our jar, that is milk to the line, then one slightly heaped lid of oats.
No chia? Use about 130ml of milk instead.
What is the ratio of oats to milk for overnight oats?
Our house ratio is 50g rolled oats to 150ml milk, plus 1 tbsp chia seeds. It carries more milk than the old equal-volumes rule because the chia soaks up about 20ml of milk as it sets. Leave the chia out and 50g of oats wants about 130ml instead.
We built the ratio into our overnight oats jar: one slightly heaped lid holds about 50g of oats, and the milk line sits at 150ml, with markings up to 300ml. No jar with markings? A kitchen scale and a measuring jug get you to the same place.
Milk to the line, then one slightly heaped lid of oats and 1 tbsp chia. Stir, seal, and chill overnight.
Why measure overnight oats in grams, not cups?
The classic internet rule is equal volumes: ½ cup of oats to ½ cup of milk. In real measurements that is roughly 45g of oats to 120ml of milk per ½ cup scoop.
The trouble is the scoop. A ½ cup of rolled oats weighs 40g to 45g depending on how the flakes settle, so the same recipe can come out thick one day and loose the next. Milk behaves by volume; oats do not. Weigh the oats, measure the milk, and the jar comes out the same every time.
How many oats and how much milk for 2 jars or a batch?
The ratio scales in straight lines: multiply everything by the number of jars.
| Jars | Rolled oats | Milk | Chia seeds |
|---|---|---|---|
| 1 jar | 50g | 150ml | 1 tbsp |
| 2 jars | 100g | 300ml | 2 tbsp |
| 3 jars | 150g | 450ml | 3 tbsp |
| Batch of 4 | 200g | 600ml | 4 tbsp |
Mix a batch in a bowl and divide it between jars, or skip the bowl and build each jar on its own: milk to the line, then one slightly heaped lid of oats and 1 tbsp chia.
How much milk for overnight oats?
Use 150ml of milk for every 50g of rolled oats, with 1 tbsp chia. Other oats, and other liquids, change the amount.
| What you use | Milk per 50g of oats | What to expect |
|---|---|---|
| Rolled oats | 150ml, to the line | The standard. Use the ratio as written. |
| Jumbo oats | 150ml, or 160ml for a softer set | Stays chewier. Give it the full 8 hours. |
| Instant or porridge oats | About 130ml | Absorbs faster and sets softer. |
| Steel-cut oats | Not recommended | Stays hard on an overnight soak. |
| No chia seeds | About 130ml | Drop the 20ml the chia would take up. |
| Water instead of milk | The same, to the line | Thinner and less creamy. |
Do add-ins change the amount of milk?
- Chia seeds. Every 1 tbsp takes up about 20ml of milk, which is why the house ratio runs at 150ml rather than 130ml.
- Greek yoghurt. 1 tbsp makes a noticeably thicker jar. Loosen it with a splash of milk in the morning if it needs it.
- Mashed banana or grated apple. A whole mashed banana adds moisture, so the jar sets a little softer, but the milk still goes to the line. With grated apple, or half a banana, the milk stays the same too.
Overnight oats too thick or too runny?
- Too thick: stir in a splash of milk in the morning until it loosens. Nothing else needed.
- Too runny: instant oats and skipped chia both loosen the set. Add 1 tsp of chia seeds, stir, and give it 20 minutes to set.
Wondering whether a jar from earlier in the week is still good? See how long overnight oats last.
Your questions
Can you make overnight oats with water instead of milk?
Yes. The oats still set overnight, but the result is thinner and less creamy. Half milk and half water is the compromise if you are short on milk. For a richer jar without dairy, use a creamier plant milk, such as oat, to the same 150ml line.
Do jumbo oats need a different ratio to rolled oats?
Jumbo oats use the same ratio as rolled oats, 50g to 150ml milk with 1 tbsp chia, but the bigger flakes absorb more slowly and stay chewier. Give them the full 8 hours in the fridge, and if you prefer a softer jar, add an extra 10ml of milk.
Keep reading
Strawberry Cheesecake Overnight Oats
Cream cheese, strawberries, and a biscuit crunch
Blueberry and Lemon Overnight Oats
Lemon zest and blueberries, bright and fresh
Blended Berry Overnight Oats
Blended smooth, with no oaty bits to chew