Use the Macro calculator
How this Macro calculator works
This calculator uses the Mifflin–St Jeor equation to estimate your Basal Metabolic Rate (BMR), multiplies by an activity factor to reach Total Daily Energy Expenditure (TDEE), and then applies a calorie surplus or deficit based on your goal. Macros are then split in grams using the protein / carb / fat percentages you choose, so you get a concrete plan you can actually follow.
Calculation method
BMR uses Mifflin–St Jeor; TDEE applies a sedentary (1.2), light (1.375), moderate (1.55), active (1.725) or very active (1.9) multiplier. Fat-loss and muscle-gain goals shift calories by a percentage of TDEE scaled by your chosen speed (1–5). Macros are computed from the three percentages you supply: protein has 4 kcal/g, carbs have 4 kcal/g, fat has 9 kcal/g.
Real-life uses
- Starting a fat-loss phase and wanting a realistic calorie target
- Setting protein and carb targets before building a meal plan
- Sanity-checking a tracker app's daily calorie estimate
- Adjusting calories during a deliberate muscle-gain phase
Frequently asked questions
Is this medical advice?
No. It is a planning estimate based on published equations and should not replace professional dietary advice.
How accurate is BMR from Mifflin–St Jeor?
Within about 10% for most healthy adults. Very athletic or very sedentary users may need to adjust calories up or down after 2–3 weeks.
How do I pick goal speed?
A speed of 3 gives a moderate change. Higher speeds create a larger deficit or surplus but are harder to sustain.
Can I send the targets to Meal Planner?
Yes. Signed-in users with the bundle can push the calorie and macro targets straight into the Meal Planner preferences used to build recipe plans.