Calculator Form
This tool supports BMI, BMR, maintenance calories, goal calories, healthy weight range, BMI Prime, ponderal index, and basic macro planning.
Example Data Table
| Profile | Sex | Age | Height | Weight | BMI | BMR | Maintenance |
|---|---|---|---|---|---|---|---|
| Office Worker | Male | 30 | 175 cm | 70 kg | 22.86 | 1,649 | 2,556 |
| Runner | Female | 28 | 165 cm | 58 kg | 21.30 | 1,320 | 2,046 |
| Strength Trainee | Male | 35 | 180 cm | 88 kg | 27.16 | 1,835 | 3,164 |
Formula Used
BMI Formula
BMI = weight in kilograms ÷ height in meters²
Mifflin-St Jeor BMR
Male: BMR = 10 × kg + 6.25 × cm − 5 × age + 5
Female: BMR = 10 × kg + 6.25 × cm − 5 × age − 161
Harris-Benedict Revised BMR
Male: BMR = 88.362 + 13.397 × kg + 4.799 × cm − 5.677 × age
Female: BMR = 447.593 + 9.247 × kg + 3.098 × cm − 4.330 × age
Katch-McArdle BMR
BMR = 370 + 21.6 × lean body mass in kg
Maintenance Calories
TDEE = BMR × activity multiplier
How to Use This Calculator
- Select your preferred unit system.
- Enter age, sex, height, and weight.
- Choose your activity level for daily energy estimation.
- Select a BMR formula. Add body fat for Katch-McArdle.
- Choose a goal such as maintenance, fat loss, or muscle gain.
- Press the calculate button to view the result above the form.
- Review BMI, BMR, maintenance calories, goal calories, and weight range.
- Use the export buttons to save your result as CSV or PDF.
Frequently Asked Questions
1. What does BMI measure?
BMI estimates body size by comparing weight with height. It is useful for screening, but it does not directly measure body fat, muscle, or health status.
2. What does BMR mean?
BMR means Basal Metabolic Rate. It estimates how many calories your body needs each day at complete rest for basic life functions.
3. Which BMR formula should I choose?
Mifflin-St Jeor is commonly used for general estimates. Harris-Benedict is another classic option. Katch-McArdle is helpful when body fat percentage is known.
4. Why can two formulas give different BMR values?
Each equation was developed from different study populations and assumptions. Small differences are normal, so results should be treated as estimates, not exact numbers.
5. Is BMI accurate for athletes?
Not always. Athletic people may have higher muscle mass, which can raise BMI without reflecting excess body fat. In such cases, body fat data helps more.
6. What is maintenance calories?
Maintenance calories estimate how much energy you need to keep your current weight stable, based on your BMR and activity level.
7. Should I use this tool for medical diagnosis?
No. This calculator is for education and planning. It does not replace clinical assessment, medical diagnosis, or personalized advice from a qualified professional.
8. How often should I recalculate BMI and BMR?
Recalculate whenever weight, activity, age, or body composition changes meaningfully. Monthly checks are usually enough for most planning purposes.