Calculate heart rate training zones by age. Find your target heart rate ranges for different exercise intensity levels. Everything runs locally in your browser — nothing is uploaded.
Calculates Basal Metabolic Rate using the Mifflin-St Jeor equation with age, sex, height, and weight. Nutritionists use it for diet planning. Everything runs locally in your browser — nothing is uploaded.
Calculate BMI for children with age and gender considerations. Track childhood growth and weight status. Everything runs locally in your browser — nothing is uploaded.
Calculate daily baby formula amount based on weight and age. Get recommended ounces and milliliters per feeding. Everything runs locally in your browser — nothing is uploaded.
Convert time between different time zones. Enter a time and your source/target time zones and see the converted result. Everything runs locally in your browser — nothing is uploaded.
Calculate exact age in years, months, and days from a date of birth in DD/MM/YYYY format. Includes eligibility check for Indian government age requirements.
Max HR ≈ 220 − age (rough) or 207 − 0.7 × age (better fit over 40). Zones: 50–60% recovery, 60–70% fat-burn, 70–80% aerobic, 80–90% threshold, 90–100% max. Example: age 30 → max ≈186, Zone 2 ≈112–130 bpm.
Zone 2 (60–70%) burns the highest fat fraction — but higher zones burn more total calories per minute. For fat loss, total weekly volume in Zones 2–3 beats short Zone 5 bursts.
±10–12 bpm for most people; medications (beta blockers), fitness, and genetics shift it. For precise training, do a field test or lab VO2max — formulas are starting points.
80% of runs in Zone 2 (conversational pace), 20% harder. Beginners going too hard is the top cause of burnout and injury — slow builds the aerobic base.
No. All calculations run locally in your browser. No health data is transmitted or stored.
Running Pace Calculator
Calculate running pace from distance and time. Enter your run details to find pace per kilometer and speed in km/h. Everything runs locally in your browser — nothing is uploaded.
Calories Burned Calculator
Estimate calories burned during exercise. Supports running, walking, cycling, swimming, yoga, lifting, and jump rope activities. Everything runs locally in your browser — nothing is uploaded.