Free oatmeal serving calculator. Enter servings to find the oats in grams and the water in millilitres you need for breakfast oatmeal.
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Enter servings. This oatmeal serving calculator plans 50 grams of oats and 200 ml of water per serving, a 1 to 4 oats to water ratio by weight and volume in this calculator, so 4 servings need 200 grams of oats and 800 ml of water. Rolled oats, steel cut oats and instant oats use different ratios, so check the type table below if you are not using rolled oats.
Fifty grams of oats makes a filling bowl, about 200 grams of cooked oatmeal. This porridge recipe guide gives quantities and ingredients for each serving size. Use 40 grams for a light serving, 50 grams for a standard serving, and 60 grams for a very hungry eater. Competitor serving weights tables agree closely: small 25 grams, medium 40 grams, large 55 grams, and extra large 75 grams. This calculator uses 50 grams as its standard, between medium and large, so it suits most adults. Children usually need about 25 to 33 grams, about one third of a cup of oats.
The standard rolled oats water ratio is 1 part oats to 2 parts liquid by volume: half a cup of oats to 1 cup of water or milk for one serving. That cup of liquid is about 240 ml, so a 50 gram serving with 200 ml of water in this calculator sits close to the same creamy result, with a slightly thicker bowl. Water gives the purest oat flavour and scorches least, milk makes the bowl creamier, and half water with half milk is the compromise most cooks land on. Add a pinch of salt every time, even for sweet oatmeal, since salt lifts oat flavour without tasting salty.
Steel cut oats are denser and need far more liquid and time than rolled oats. The steel cut oats water ratio is about 1 part oats to 4 parts water for stovetop cooking, simmered gently for 20 to 30 minutes, or 1 part oats to 2.5 parts liquid in some slow cooker guides. A quarter cup of steel cut oats needs about 1 cup of water, and a full cup needs about 4 cups. Soaking steel cut oats overnight cuts cooking time by about half and gives a chewier, nuttier bowl than rolled oats. Never use the rolled oats ratio for steel cut oats, or the bowl will stay hard in the middle.
Instant oats are pre-cooked and cut finer, so they need the least liquid: about 1 part oats to 1 part water, or half a cup of water for half a cup of instant oats. Quick oats sit between instant and rolled oats, at about 1 part oats to 2 parts water, the same as rolled oats, but they cook faster and go softer. If instant oatmeal overflows in the microwave, use a larger bowl, stir halfway, and let it stand for 1 to 2 minutes after cooking. Instant oats thicken fast, so serve at once rather than letting the bowl sit.
Overnight oats need no cooking: mix oats with milk or water and chill them overnight. The overnight oats ratio is usually 1 part oats to 2 parts milk for rolled oats, or 1 part steel cut oats to 2 parts milk for steel cut overnight oats, left for at least 4 hours and ideally 12 hours. Add chia seeds, yoghurt or nut butter in the morning for thickness, and fruit on top for sweetness. Overnight oats keep well in jars for meal prep, and they suit hot mornings when a hot bowl feels too heavy.
Weighing oats beats scooping them, because cups measure volume and oat flakes pack differently each time. A serving weights table helps: 25 grams is small, 40 grams is medium, 55 grams is large, and 75 grams is extra large. For milk or water, the matching amounts are about 172 ml for 25 grams, 275 ml for 40 grams, 378 ml for 55 grams, and 516 ml for 75 grams at an average consistency, or a little less for a thicker bowl. This calculator uses 50 grams with 200 ml, a thicker, spoonable bowl, so add a splash of milk at the table if you prefer it looser.
Oatmeal scales cleanly: multiply servings by 50 grams of oats and 200 ml of water. Ten servings need 500 grams of oats and 2000 ml of water, and 20 servings need 1000 grams and 4000 ml. Cook a crowd batch in a large pot, not a small saucepan, since oatmeal bubbles up and can boil over. Stir often, keep the heat low once it simmers, and hold the cooked oatmeal covered for up to 30 minutes, adding a splash of hot water before serving if it thickens. Set toppings out separately, so each person seasons their own bowl.
Toppings turn a plain bowl into breakfast: fruit, berries, banana, honey, maple syrup, nuts, seeds, cinnamon, yoghurt or a splash of cream. Add wet fruit after cooking, not before, since wet fruit dilutes the bowl. For milk or water, water is cheapest and lightest, dairy milk adds protein and creaminess, oat milk doubles the nutty flavour, soy milk adds protein, and coconut milk turns the bowl into dessert, so thin canned coconut milk 1 to 1 with water. Keep toppings simple for weekday bowls and save elaborate toppings for weekends.
About 50 grams of oats with 200 ml of water per serving in this calculator. Competitor tables put a medium serving at 40 grams and a large serving at 55 grams.
About 200 grams of oats with 800 ml of water. For 10 servings, use 500 grams of oats with 2000 ml of water.
For rolled oats, 1 part oats to 2 parts liquid by volume: half a cup of oats to 1 cup of water. This calculator uses 50 grams with 200 ml for a thicker bowl.
About 1 part oats to 4 parts water for stovetop cooking, simmered for 20 to 30 minutes. Soaking overnight cuts the cooking time by about half.
About 1 part oats to 1 part water. Instant oats are pre-cooked, so they need less liquid and cook in about 2 minutes.
About 1 part oats to 2 parts milk, chilled for at least 4 hours and ideally overnight. Steel cut overnight oats use the same 1 to 2 ratio.
Yes. Milk makes oatmeal creamier and adds protein, but it can scorch, so use low heat and stir often. Half water and half milk is a good compromise.
Fruit, berries, banana, honey, maple syrup, nuts, seeds, cinnamon and yoghurt. Add toppings after cooking so wet fruit does not dilute the bowl.