Calculator Inputs
Example Data Table
These sample rows show how different activity patterns and methods can affect maintenance planning.
| Profile | Method | Activity Factor | Exercise Plan | Estimated AMR | Goal Calories |
|---|---|---|---|---|---|
| Male, 30y, 78 kg, 178 cm | Mifflin-St Jeor | 1.55 | 6 MET, 45 min, 4 times weekly | 2,886 kcal/day | 2,386 kcal/day |
| Female, 27y, 62 kg, 165 cm | Mifflin-St Jeor | 1.375 | 5 MET, 35 min, 3 times weekly | 2,022 kcal/day | 2,272 kcal/day |
| Male, 35y, 85 kg, 18% fat | Katch-McArdle | 1.725 | 8 MET, 60 min, 5 times weekly | 3,487 kcal/day | 3,237 kcal/day |
Formula Used
1) Mifflin-St Jeor BMR
Male: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Female: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
2) Katch-McArdle BMR
Lean Body Mass = weight × (1 − body fat % / 100)
BMR = 370 + 21.6 × lean body mass(kg)
3) Lifestyle Calories
Lifestyle Calories = BMR × activity factor
4) Exercise Calories
Average exercise hours per day = (minutes per session × sessions per week ÷ 60) ÷ 7
Exercise Calories = MET × weight(kg) × average exercise hours per day
5) Thermic Effect and Active Metabolic Rate
Pre-TEF Total = Lifestyle Calories + Exercise Calories
TEF Calories = Pre-TEF Total × thermic effect %
Active Metabolic Rate = Pre-TEF Total + TEF Calories
6) Goal Calories
Goal Calories = Active Metabolic Rate + preset adjustment + custom adjustment
How to Use This Calculator
- Enter sex, age, weight, and height.
- Choose the preferred BMR method or leave Auto selected.
- Add body fat percentage when using Katch-McArdle.
- Select your general lifestyle activity factor.
- Enter exercise MET, session minutes, and weekly frequency.
- Set a thermic effect percentage for digestion-related calories.
- Choose a goal strategy and add any custom calorie adjustment.
- Click the calculate button to see maintenance and target calories.
- Download the result as CSV or PDF when needed.
Frequently Asked Questions
1) What does active metabolic rate mean here?
It means your estimated daily maintenance calories after resting metabolism, lifestyle activity, planned exercise, and thermic effect are combined into one planning value.
2) Which BMR formula should I use?
Use Mifflin-St Jeor for most people when body fat is unknown. Use Katch-McArdle when you have a reliable body fat estimate and want lean-mass-based BMR.
3) What is a MET value?
MET is a standard measure of activity intensity. Higher MET values mean more energy use. Brisk walking is lower than hard running or intense cycling.
4) Why include thermic effect?
Thermic effect reflects calories used to digest, absorb, and process food. Including it can give a more complete estimate of daily maintenance energy needs.
5) Can I use this for weight loss planning?
Yes. Choose a negative adjustment or select a loss preset. The result gives a practical calorie target, but progress should still be reviewed against actual weekly trends.
6) Why is my weekly weight change only an estimate?
Real weight change depends on water balance, adherence, training load, hormones, medications, and metabolic adaptation. The calculator uses a simplified energy model for planning.
7) Should athletes trust the result exactly?
Athletes can use it as a starting point, but heavy training, recovery demands, and sport season changes may require higher precision through tracking and professional review.
8) Is this calculator a medical tool?
No. It is an educational planning calculator. People with medical conditions, pregnancy, eating disorders, or therapeutic diet prescriptions should consult a qualified clinician.