Body Composition
9 free calculators & converters. Every tool runs entirely in your browser — nothing you type is uploaded.
Available calculators
BMI Calculator
Free BMI calculator: estimate your Body Mass Index and category instantly. Uses the standard WHO BMI formula. No sign-up required.
BMR Calculator (Mifflin-St Jeor)
Free BMR calculator using the Mifflin-St Jeor equation. Calculate how many calories your body burns at complete rest. Accurate for most adults.
Body Fat Percentage Calculator
Free body fat calculator using the US Navy method. Enter height and body circumference measurements to estimate body fat percentage — no calipers needed.
Body Surface Area (BSA) Calculator
Calculate Body Surface Area (BSA) using 5 formulas: Du Bois, Mosteller, Haycock, Gehan-George, Boyd. Used in medicine, nutrition, and fitness.
Body Type Calculator
Discover your body type (ectomorph, mesomorph, endomorph) based on wrist, waist, hip, shoulder measurements and visual cues.
Reverse BMI Calculator
Enter your height and target BMI to find your ideal goal weight. Works for both metric (cm/kg) and imperial (ft/lbs) units.
Lean Body Mass Calculator
Free lean body mass calculator. Enter your weight and body fat percentage to estimate how much of your weight is lean tissue vs fat mass.
Ideal Weight Calculator
Estimate your ideal healthy weight range based on height, gender, and body frame. Uses three evidence-based formulas (Devine, Robinson, Miller).
Waist-to-Height Ratio Calculator
Free waist-to-height ratio calculator. More accurate than BMI for health risk assessment in many people — measure waist and height only.
About the Body Composition
All 9 free body composition calculators and converters at mQuickCalc Health. No sign-up, no email, no data collected. The tool runs entirely in your browser, so nothing you enter is uploaded or stored.
Choosing the right tool
- BMI Calculator — Free BMI calculator: estimate your Body Mass Index and category instantly. Uses the standard WHO BMI formula. No sign-up required.
- BMR Calculator (Mifflin-St Jeor) — Free BMR calculator using the Mifflin-St Jeor equation. Calculate how many calories your body burns at complete rest. Accurate for most adults.
- Body Fat Percentage Calculator — Free body fat calculator using the US Navy method. Enter height and body circumference measurements to estimate body fat percentage — no calipers needed.
- Body Surface Area (BSA) Calculator — Calculate Body Surface Area (BSA) using 5 formulas: Du Bois, Mosteller, Haycock, Gehan-George, Boyd. Used in medicine, nutrition, and fitness.
- Body Type Calculator — Discover your body type (ectomorph, mesomorph, endomorph) based on wrist, waist, hip, shoulder measurements and visual cues.
- Reverse BMI Calculator — Enter your height and target BMI to find your ideal goal weight. Works for both metric (cm/kg) and imperial (ft/lbs) units.
- Lean Body Mass Calculator — Free lean body mass calculator. Enter your weight and body fat percentage to estimate how much of your weight is lean tissue vs fat mass.
- Ideal Weight Calculator — Estimate your ideal healthy weight range based on height, gender, and body frame. Uses three evidence-based formulas (Devine, Robinson, Miller).
- Waist-to-Height Ratio Calculator — Free waist-to-height ratio calculator. More accurate than BMI for health risk assessment in many people — measure waist and height only.
For general information only, not medical advice — see our disclaimer.
Frequently asked questions
How do I calculate my BMI?
BMI = weight (kg) / height (m)^2. A BMI of 18.5-24.9 is healthy, 25-29.9 is overweight, and 30+ is obese. The BMI calculator handles kg/lbs and metric/imperial.
How do I measure my body fat percentage?
The US Navy method uses neck, waist and hip circumference. The body fat calculator estimates it in seconds. Healthy ranges are 14-20% for men and 21-33% for women.
What is a healthy waist-to-height ratio?
Aim for under 0.5, your waist should measure less than half your height. The waist-to-height calculator checks your risk level and is considered more accurate than BMI alone.