Fitness Calculators: BMI, Body Fat, Calories and Training Zones
Whether you are preparing for a recruitment physical or just tracking your training, these calculators estimate body composition, energy needs and exercise intensity from a few measurements. Results are estimates based on standard formulas, so use them as a guide rather than a medical assessment.
12 free fitness calculators
BMI Calculator
Body Mass Index from height and weight.
Open calculator →Calorie Calculator
Daily calorie target for a weight-loss, maintenance or gain goal.
Open calculator →Body Fat Calculator
Estimated body fat % using the US Navy circumference method.
Open calculator →BMR Calculator
Calories burned at complete rest (Mifflin-St Jeor equation).
Open calculator →Ideal Weight Calculator
Ideal body weight for your height, from four classic formulas.
Open calculator →Pace Calculator
Running or cycling pace and speed, from distance and time.
Open calculator →Army Body Fat Calculator
Tape-test-style body fat estimate against age-banded standards.
Open calculator →Lean Body Mass Calculator
Estimated fat-free body mass (Boer formula).
Open calculator →Healthy Weight Calculator
Healthy weight range for your height (normal BMI band).
Open calculator →Calories Burned Calculator
Calories burned during an activity, using MET values.
Open calculator →One Rep Max Calculator
Estimated 1-rep max, plus target weights for other rep ranges.
Open calculator →Target Heart Rate Calculator
Training heart-rate zones from age (and optionally resting HR).
Open calculator →Frequently asked questions
Are fitness calculator results exact?
No. They use population-level formulas, so they are estimates. For medical decisions consult a healthcare professional.