🔥 Katch-McArdle Calculator
Estimate your basal metabolic rate (BMR) with the Katch-McArdle formula, which uses your lean body mass for a more personalized result than weight-only formulas.
What is the Katch-McArdle formula?
The Katch-McArdle formula estimates basal metabolic rate (BMR), the number of calories your body burns at complete rest, using your lean body mass rather than your total body weight. Because it accounts for body composition, it can be more accurate than weight-only formulas for people who know their body fat percentage, especially those who are more muscular or leaner than average.
The formula
Lean Body Mass (LBM) = Weight × (1 − Body Fat % ÷ 100). BMR = 370 + (21.6 × LBM in kg). The calculator also multiplies your BMR by an activity factor to estimate your total daily energy expenditure (TDEE), the approximate number of calories you burn per day including activity.
Accuracy depends heavily on how accurately you know your body fat percentage; methods like calipers, bioelectrical impedance scales, or DEXA scans give different estimates. This tool is for general fitness planning and educational purposes only and is not medical advice.