Clinical-Grade Fitness & Metabolic Calculators
Scientifically calibrated algorithms for body composition, metabolic expenditure, cardiovascular training zones, barbell strength, and circadian recovery—executing 100% privately in your browser.
Health & Performance Tools (10 Free Calculators)
Select any tool below for instant, private physiological calculations without account signups or data tracking.
US Navy Body Fat Calculator
Circumference method using neck, waist, height, and hip measurements in inches per DoD Directive.
TDEE Calculator & Macro Calorie Splitter
Mifflin-St Jeor equation determining BMR, activity multiplier, and customizable carb/protein/fat splits.
Daily Water Intake Calculator (Fluid Ounces)
Fluid ounces calculation based on body weight in lbs, climate conditions, and exercise intensity minutes.
One-Rep Max (1RM) Strength Calculator
Brzycki, Epley, and Lander formulas calculating 1RM across Barbell Bench Press, Squat, and Deadlift.
Running Pace & Race Finish Time Estimator
Pace in min/mile vs min/km targeting 5K, 10K, Half-Marathon, and Marathon finish benchmarks.
Target Heart Rate Zones (Karvonen Method)
Karvonen formula deriving Zone 1 to Zone 5 cardiovascular thresholds based on resting and max heart rate.
Sleep Cycle & 90-Minute Circadian Calculator
90-minute circadian sleep cycle calculator suggesting ideal wake-up or bedtimes to eliminate grogginess.
Intermittent Fasting Timer & Protocol Tracker
16:8, 18:6, and 20:4 timer persisting elapsed hours in client-side localStorage with stage milestones.
Pregnancy Due Date Calculator (Naegele's Rule)
Naegele's rule based on Last Menstrual Period (LMP) and ultrasound cycle offsets for estimated delivery dates.
Calorie Deficit & Goal Weight Date Predictor
Dynamic forecast date to reach goal weight assuming standard 3,500 kcal per pound fat loss deficit modeling.
The Principles of Evidence-Based Human Conditioning
Sustainable physical transformation and athletic conditioning require an unyielding adherence to thermodynamics and human bioenergetics. Whether determining your basal metabolic expenditure with the Mifflin-St Jeor equation, mapping mitochondrial fat oxidation across Karvonen Zone 2 cardio, or calculating submaximal 1RM barbell training percentages via the Brzycki formula, objective numbers eliminate guesswork.
All calculations within this suite are implemented in pure client-side TypeScript. Your sensitive personal health metrics—body weight, waist measurements, heart rate data, and fasting timestamps—never leave your local device, ensuring complete privacy compliance and zero tracking.