Biological Sex & Endocrine ProfilePhenotypic Sex Classification (Male / Female)
Drives basal hormonal scaling coefficients in empirical metabolic equations. Men possess an average of 33% greater fat-free mass (FFM) and larger organ surface area per unit stature, elevating baseline BMR by approximately 5% to 10% relative to females of identical weight and height.
Default: Male
Chronological AgePhysiological Age in Years (15 to 90)
Accounts for the clinical decline in resting metabolic rate attributable to sarcopenia (gradual skeletal muscle loss of 3% to 8% per decade post age 30) and reduced cellular mitochondrial respiration rates.
Default: 30 Years
Total Body WeightMetric Kilograms (kg) or Imperial Pounds (lbs)
Primary gross mass variable in all BMR equations. Higher overall body mass incurs an increased metabolic upkeep cost at rest and increases mechanical energetic demands during all weight-bearing locomotion.
Default: 75.0 kg / 165.3 lbs
Stature HeightMetric Centimeters (cm) or Imperial Feet & Inches
Determines body surface area via the Du Bois geometric relationship. Taller statures present larger skin surface areas, increasing passive radiative thermoregulatory heat dissipation and resting caloric demand.
Default: 175 cm / 5 ft 9 in
Body Fat Percentage & Lean MassAdipose Mass Ratio (4.0% to 55.0%)
Clinical parameter enabling the Katch-McArdle equation by isolating Fat-Free Mass (FFM). Skeletal muscle, internal organs, and bone tissue exhibit metabolic activity rates of 13 to 200 kcal/kg/day, whereas inactive adipose lipid droplets burn merely 4.5 kcal/kg/day.
Default: 18.0%
Physical Activity Level (PAL)FAO/WHO Activity Factor (1.20 to 1.90)
Standardized physiological ratio multiplying BMR to capture total daily movement: 1.20 (Sedentary desk job, <4,000 steps), 1.375 (Light activity, 4,000-7,000 steps, 1-3 workouts/week), 1.55 (Moderate activity, 7,000-10,000 steps, 3-5 workouts/week), 1.725 (Heavy activity, 10,000-14,000 steps, 6-7 intense sessions), and 1.90 (Athlete / Heavy labor, >14,000 steps or two-a-day training).
Default: 1.375 (Light Activity)
Target Caloric AdjustmentDaily Energy Delta (-1000 kcal to +1000 kcal/day)
The deliberate energy imbalance enforced relative to TDEE. A 500 kcal daily deficit translates to approximately 3,500 kcal per week (~0.45 kg / 1 lb of adipose tissue energy density), while a 250 to 300 kcal surplus supports myofibrillar protein synthesis with minimal de novo lipogenesis.
Default: -500 kcal/day (Standard Cut)
