Meal prep macro calculator
Find your daily calories and macros, then see exactly what each prepped container should hold. Uses the Mifflin–St Jeor equation, the same one most dietitians start with.
Fine-tune protein and fat
BMR 1,429 kcal · TDEE 2,215 kcal
Per container
each box 905 kcal · 46 g protein · 120 g carbs · 27 g fat
Where your calorie number comes from
Step through it with your own numbers. Change the form above and the bars follow.
Resting energy (BMR)
What your body burns lying still for 24 hours: heart, brain, breathing, keeping warm. Mifflin–St Jeor: 10 × kg + 6.25 × cm − 5 × age, then +5 for men or −161 for women.
How to use your macros for meal prep
Daily targets are hard to hit meal by meal, but easy to hit container by container. Once each box is built to the per-container number above, the week takes care of itself: eat the boxes, add breakfast and a snack from your reserve, done.
- Build around protein. It's the macro people miss. Weigh the raw protein for the batch first (see raw vs cooked weight), then add carbs to reach the calorie number.
- Log the recipe once, as a batch. Enter the raw ingredients, then divide by containers. The container calculator splits the pot by weight so every box really is equal.
- Check the trend after two weeks. The equation is an estimate. If the scale isn't moving the way you want, change calories by 100–200 a day and keep everything else the same.
Protein needs get their own deep dive in the protein calculator, including per-meal amounts and food swaps.
Questions people ask
How does a macro calculator work?
It estimates your resting energy with the Mifflin–St Jeor equation, multiplies by an activity factor to get total daily energy expenditure (TDEE), adjusts for your goal, then splits the calories: protein first (grams per kg of body weight), fat as a share of calories, and carbohydrate fills the rest.
How many calories should I eat a day?
Roughly your TDEE to maintain weight, about 15–25% less to lose fat, and 5–10% more to gain muscle slowly. The calculator gives a starting point; weigh yourself for 2–3 weeks and adjust by 100–200 kcal if the trend is not moving the way you want.
How do I turn daily macros into meal prep containers?
Divide the daily numbers by how many meals come from containers. If you eat 2,100 kcal and 150 g protein and prep lunch and dinner, and keep about 500 kcal for breakfast and snacks, each container should hold about 800 kcal and 60 g protein.
Is the Mifflin–St Jeor equation accurate?
It is the equation the Academy of Nutrition and Dietetics found most accurate for healthy adults, typically within about 10% of measured resting energy for most people. Very muscular or very heavy people can fall outside that range.
Why is protein set per kilogram and not as a percentage?
Protein needs scale with body mass, not with calories. The International Society of Sports Nutrition suggests 1.4–2.0 g/kg per day for active people, and higher intakes help keep muscle during a calorie deficit. A percentage would give too little on a cut and too much on a bulk.