Fitness & Performance
Katch-McArdle TDEE Calculator
Standard TDEE formulas under-serve muscular bodies. This one runs the whole calculation on lean mass instead.
Katch-McArdle TDEE starts from lean body mass: BMR = 370 + 21.6 × lean kg, then multiplies by an activity factor from 1.2 to 1.9. It is the preferred energy estimate for athletes and muscular builds. Use the result as a training benchmark — retest under the same conditions to track progress.
BMR = 370 + 21.6 × lean kg.
More accurate for trained bodies.
Cut −15–20% · gain +10–15%.
Calculate Your Katch-McArdle TDEE
Your TDEE
What Is Katch-McArdle TDEE?
Lean mass does essentially all of the body's resting metabolic work, so basing TDEE on it removes the main error in standard formulas — muscle being counted as 'excess weight'.
This calculator chains the Katch-McArdle BMR with the standard activity multipliers, giving trained individuals the energy estimate that matches their actual burn.
How It Is Calculated
LBM = weight × (1 − body fat % ÷ 100)
BMR = 370 + 21.6 × LBM
TDEE = BMR × activity factor (1.2–1.9)
Example: Example: 80 kg at 15% fat → 68 kg LBM → BMR 1,839 × 1.55 → TDEE ≈ 2,850 kcal
Katch vs standard estimates (80 kg, 15% fat, active)
| Method | TDEE |
|---|---|
| Katch-McArdle | ≈ 2,850 kcal |
| Mifflin-St Jeor (male, 30, 178 cm) | ≈ 2,720 kcal |
| Difference | +130 kcal — muscle finally counted |
Limitations
- Body-fat input drives accuracy — use a consistent measurement method.
- Same activity-factor caveats apply: people overestimate their level.
- Extremes of body fat reduce formula reliability.
Sources & Review
References used for this calculator’s formulas and thresholds:
Katch-McArdle TDEE FAQ
Why use Katch-McArdle TDEE?
Standard formulas under-estimate muscular people. Lean-mass-based TDEE typically runs 5–10% higher for trained bodies — and matches their real burn.
How is it different from the Katch BMR tool?
This is the full energy picture: Katch BMR multiplied by activity — the number you actually eat against.
What body fat input should I use?
The same one consistently — Navy tape or skinfold both work; the formula tolerates ±3% error well.
Important disclaimer: Results are educational estimates, not a substitute for professional professional advice. Discuss your results with a qualified professional before making decisions.