Calculator Inputs
Example Data Table
| Profile | Weight | Height | Activity | Goal | Estimated Use |
|---|---|---|---|---|---|
| Beginner Cut | 180 lb | 5 ft 10 in | Moderate | -20% | Fat loss phase |
| Lean Bulk | 165 lb | 5 ft 9 in | Hard | +10% | Muscle gain phase |
| Maintenance | 72 kg | 176 cm | Light | 0% | Weight stability |
Formula Used
Mifflin-St Jeor:
Men: BMR = 10W + 6.25H - 5A + 5
Women: BMR = 10W + 6.25H - 5A - 161
Revised Harris-Benedict:
Men: BMR = 88.362 + 13.397W + 4.799H - 5.677A
Women: BMR = 447.593 + 9.247W + 3.098H - 4.330A
Katch-McArdle:
BMR = 370 + 21.6 × lean body mass in kg
W means weight in kilograms. H means height in centimeters. A means age in years. TDEE equals BMR multiplied by activity factor. Target calories equal TDEE adjusted by your selected goal percentage.
How to Use This Calculator
- Choose your unit system first.
- Enter your sex, age, weight, and height.
- Add body fat percentage if you know it.
- Select a formula, or keep auto mode.
- Choose your activity level.
- Pick cutting, maintenance, lean bulk, or custom goal.
- Adjust protein and fat targets if needed.
- Press the calculate button to view results.
- Use CSV or PDF export for saving your plan.
BMR Planning for Bigger, Leaner, Stronger Progress
Why BMR Matters
BMR is your baseline energy cost. It estimates calories used at rest. This number is not your full daily burn. It is only the starting point. A good nutrition plan begins with this estimate. Then activity is added. The result is your total daily energy expenditure. That number guides your diet.
From Baseline to Goal Calories
The bigger, leaner, stronger approach needs structure. Cutting requires a sensible deficit. Maintenance needs stable intake. Lean bulking uses a small surplus. Large changes can work for short periods. They can also reduce adherence. A smaller, measured change is often easier to repeat.
Using Lean Mass
Body composition improves the estimate. Katch-McArdle uses lean body mass. That makes it useful for trained lifters. It can also help during fat loss. If body fat is unknown, Mifflin-St Jeor is a reliable choice. This calculator compares formulas, so you can review the spread.
Macro Targets
Calories control weight change. Macros control diet quality and training support. Protein helps preserve muscle. Fat supports hormones and meal satisfaction. Carbohydrates fill the remaining calories. They also fuel hard training. The meal split helps you plan each day. It does not force strict timing.
Best Practical Use
Treat the result as a starting estimate. Track body weight for two weeks. Compare the trend with your goal. If weight changes too fast, adjust calories. If weight stalls, adjust again. Small updates are better than random changes. Use strength, energy, hunger, and measurements as extra feedback.
FAQs
1. What does BMR mean?
BMR means basal metabolic rate. It estimates calories your body uses at rest for basic functions like breathing, circulation, and temperature control.
2. Is BMR the same as TDEE?
No. BMR is resting energy use. TDEE adds daily movement and exercise through an activity multiplier.
3. Which formula should I choose?
Use auto mode for most cases. It uses Katch-McArdle when body fat is provided, otherwise it uses Mifflin-St Jeor.
4. Why does Katch-McArdle need body fat?
Katch-McArdle uses lean body mass. Body fat percentage is needed to estimate lean mass from total body weight.
5. What deficit is best for cutting?
A 15% to 25% deficit is common. Leaner people often do better with smaller deficits and careful tracking.
6. What surplus is best for lean bulking?
A small surplus near 5% to 10% is usually practical. It supports muscle gain while limiting unnecessary fat gain.
7. Should I eat the same calories daily?
You can. Weekly average calories matter most. Some lifters prefer higher calories on training days and lower calories on rest days.
8. Are these results medical advice?
No. These are fitness estimates. Speak with a qualified professional for medical, clinical, or condition-specific nutrition guidance.