Health & Fitness Calculators
Body composition, energy needs and everyday health figures worked out from the standard clinical formulas.
BMI Calculator
Work out body mass index from height and weight in metric or imperial units, see which WHO category it falls into, and read what the figure does and does not tell you.
Calorie Calculator
Estimate basal metabolic rate and daily calorie needs with the Mifflin St Jeor equation, adjusted for activity level, with targets for losing, holding or gaining weight.
Body Fat Calculator
Estimate body fat two independent ways, the US Navy tape measure method and the BMI based equation, with fat mass, lean mass and fat free mass index alongside.
Pace Calculator
Work out running pace, time or distance from the other two, with a full split table, treadmill speed and predicted times at every race distance.
Sleep Calculator
Find bedtimes that let you wake between sleep cycles rather than in the middle of one, with the time it takes to fall asleep counted separately instead of ignored.
Heart Rate Zone Calculator
Work out training zones from four different maximum heart rate formulas, using the Karvonen method when you know your resting rate, with the disagreement shown rather than hidden.
Age Calculator
Find an exact age in years, months and days from any date of birth, plus total weeks, days and hours lived and a countdown to the next birthday.
Why Choose Our Health & Fitness Calculators?
🚀 Fast & Efficient
All health & fitness calculators are optimized for speed and performance, helping you get things done quickly without compromising accuracy.
🔒 Privacy First
Your data stays in your browser. We don't store, track, or share any information you input into our health & fitness calculators.
📱 Works Everywhere
Access our health & fitness calculators from any device - desktop, tablet, or mobile. No installation required.
🆓 Always Free
No subscriptions, no hidden fees. All our health & fitness calculators are completely free to use, forever.