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Body Measurement Calculators
Body measurements can be useful for tracking a personal trend, but each method answers a different question and has limitations. This collection brings together BMI, waist-based ratios, body-fat estimates, lean body mass and ideal-weight reference tools so you can compare them with the right context.
Explore Body Measurement Calculators
11 free toolsBMI Calculator
Calculate your Body Mass Index and understand your weight category.
Body Fat Calculator
Estimate your body fat percentage using simple body measurements.
Navy Body Fat Calculator
Estimate body fat percentage using the U.S. Navy circumference method. Supports men, women, metric and imperial.
Ideal Weight Calculator
Find your healthy weight reference range based on height and BMI.
Waist-to-Height Ratio Calculator
Calculate a simple waist-to-height screening ratio.
FFMI Calculator
Calculate your Fat-Free Mass Index to estimate muscular potential.
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio (WHR) and evaluate abdominal fat distribution.
Relative Fat Mass Calculator
Estimate body-fat percentage using only height and waist measurements.
Body Frame Size Calculator
Classify your skeletal frame size and adjust ideal bodyweight targets.
Body Shape Calculator
Evaluate bust, waist, high hip, and hip measurements to identify body shape.
ABSI Calculator
Calculate A Body Shape Index from waist, height and BMI.
How to use these tools well
Understand what each measurement represents
BMI uses height and weight, while waist-based ratios add a measure of central body size. The Navy body-fat method uses circumferences and a formula, and lean-body-mass estimates depend on the inputs and equation selected. None is a direct clinical measurement of health, and different methods can reasonably give different results for the same person.
Consistency makes trends more useful
If you use a tape measure, measure at the same site, with the same posture and at a similar time of day. For body weight, compare a rolling trend rather than reacting to a single day. A consistent process makes it easier to tell whether a change is likely to be meaningful or simply normal variation from hydration, food volume or measurement technique.
Do not use a calculator as a diagnosis
These tools are designed for general fitness education and tracking. They cannot diagnose obesity, nutritional deficiency, hormonal conditions or any other health issue. A clinician can interpret measurements with medical history, symptoms and tests—context a web calculator does not have.