Overnight oats
macro calculator.

The overnight oats formula

For each labeled ingredient:

Ingredient calories = amount used ÷ label serving amount × calories per serving.

Use the same serving factor for protein, carbs, and fat. If an oats label lists 40g as one serving and you use 80g in a two-jar batch, the oats contribute two label servings to the batch and one serving to each equal jar.

Do this separately for yogurt, milk, skyr, kefir, protein powder, chia seeds, nut butter, and any packaged topping. Use USDA FoodData Central or another reliable source only when a current package label is not available.

Equal jars are easy. Uneven jars need weight.

Overnight oats are usually a repeat breakfast, which is why the math is worth doing once. If you make two identical jars, divide the batch in half. If one jar gets more yogurt, berries, peanut butter, or granola, call it a different jar instead of pretending the batch split evenly.

A finished batch weight can help when the mixture is made in one bowl first. If the bowl finishes at 720g and one jar receives 360g, that jar has half the batch. If another receives 300g, it has 300 ÷ 720 of the batch. For mixed cooked meals, use the meal prep macro calculator; for blended drinks, use the smoothie macro calculator.

The ingredients that move the number

Oats and yogurt are visible, but toppings can quietly move the result. Chia seeds, peanut butter, nuts, chocolate chips, honey, granola, and dried fruit may be small by volume and still meaningful in the calculation. Frozen berries, water, and spices change texture more than calories, but they should still be named if they help you recognize the meal later.

Recent community research pointed to practical questions: people compare oats with yogurt bowls, ask how to make breakfast filling at a given calorie level, post blended overnight oats, and discuss protein powder or chia as add-ins. That is a good match for Mori because the useful entry is a repeatable recipe, not a generic "overnight oats" database item that hides the toppings.

If the main issue is a partial powder scoop, use the protein powder scoop calculator. If you want to check how the jar fits the rest of the day, use the calories and macros remaining calculator after logging breakfast.

A cleaner Mori overnight oats entry

A useful entry includes the dry oats, the liquid or yogurt, protein powder amount, toppings, and the jar count. For example: "overnight oats batch with 80g rolled oats, 340g nonfat Greek yogurt, 16g vanilla whey, 20g chia, 140g berries, and 16g peanut butter, split into 2 jars."

That sentence gives Mori the ingredients a photo cannot know and keeps the result editable. If you make the same jars every week, save the pattern and change only the ingredient that changed: a new yogurt, half a scoop of powder, more berries, or a skipped topping.

If you are choosing an app because repeat breakfasts are the main pain, the iPhone calorie counter guide and food logging consistency guide explain why saved meals and editable estimates matter more than a pretty first result.

Evidence used for this tool

The Last30Days pass found 33 dated items across Reddit, YouTube, Hacker News, and GitHub. Reddit coverage was partial because the free route hit a rate limit, and X was not configured. The signal was still usable for workflow: oats, yogurt bowls, chia pudding, protein add-ins, and calorie-level breakfast questions appeared across recent community posts.

For factual nutrition math, this tool uses FDA serving-size guidance and USDA FoodData Central. The FDA explains that packaged-food nutrient values are tied to the serving size on the label. USDA FoodData Central is a public food composition database, useful when a plain ingredient has no product label in front of you.

What this calculator should not decide

This tool should not decide whether oats, protein powder, dairy, chia, or a specific calorie target is right for you. It cannot check allergies, eating-disorder history, diabetes care, kidney disease, pregnancy needs, medication interactions, supplement quality, or a clinician's plan.

Use it as ordinary label math for a repeat breakfast. If the numbers start to feel punitive, a simpler food note may be the better tool for that day.