Katch-McArdle BMR Calculator

Estimate BMR from lean body mass.

BMR (kcal/day) 1,838.8

Lean body mass 68

Formula: BMR = 370 + 21.6 × lean mass

Step-by-step with your numbers:

1. Values used:

2. Weight = 80

3. Body fat = 15 %

5. BMR = 1,838.8kcal/day

6. Lean body mass = 68

Did we solve your problem today?

Katch-McArdle uses lean mass, so it's accurate for lean/muscular people.

The math behind it

Lean mass = weight × (1 − body fat%); BMR = 370 + 21.6 × lean mass.

80 kg at 15% fat → LBM 68 kg → ~1,839 kcal.

Need body fat?

Yes — that's what makes it precise for athletes.