Health & Fitness Calculators

Evidence-based calculators for weight, nutrition, training, and wellness. Every tool cites the formula it uses — Mifflin-St Jeor, the U.S. Navy body fat method, Naegele's rule, and more. These tools are educational and not a substitute for professional medical advice.

Weight & Body Composition

• BMIBody mass index
• Body FatU.S. Navy method
• Ideal WeightHealthy weight range
• Lean Body MassMuscle & lean tissue

Calories & Nutrition

• BMRCalories at rest
• TDEETotal daily energy
• CalorieTo lose or gain
• Calorie DeficitDeficit size & timeline
• MacroProtein, carbs & fat
• ProteinDaily protein intake
• Water IntakeDaily hydration estimate

Fitness & Training

• Target Heart RateTraining zones
• One Rep Max (1RM)Max lift estimate
• PaceRunning pace & splits
• Calories BurnedBy activity

Pregnancy & Life

• Due DateEstimated delivery date
• OvulationFertile window estimate
• Pregnancy Weight GainHealthy gain by trimester
• BACBlood alcohol estimate
• SleepBedtimes by cycles

Medical disclaimer: Calculators in this section provide general estimates for educational purposes only. They are not medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider about your individual situation.