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BMI

Body Mass Index formulas, healthy ranges, charts, and audience-specific guidance for men, women, athletes, and every age group.

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Formula pages

BMI Formula Explained

Complete BMI formula reference with variables, units, and examples.

How-to guides

How to Calculate BMI Step by Step

Step-by-step BMI calculation with metric and imperial formulas.

Reference & charts

BMI Chart and Category Table

WHO BMI categories from underweight through obesity class III.

Healthy BMI Range by Context

Reference healthy BMI ranges with population-specific notes.

Audience guides

BMI for Men: Ranges, Limits, and What to Know

Men-specific BMI interpretation including muscle mass and visceral fat.

BMI for Women: Healthy Ranges and Pregnancy Notes

Women-specific BMI guidance including pregnancy and life-stage factors.

BMI by Age: Adults, Seniors, and Children

Age-specific BMI guidance for teens, adults, and seniors.

BMI for Athletes: When the Scale Lies

Athlete BMI limits — use FFMI and body fat instead.

Blog articles

BMI vs Body Fat: Which Metric Should You Use?

BMI is a quick screening tool based on height and weight, while body fat percentage reflects actual composition. Learn when each metric helps—and when it misleads.

Understanding BMI and Body Composition

BMI is a quick screening tool, but it does not tell the whole story. Learn when to pair it with body fat and lean mass calculators.

FAQ

Is BMI accurate for everyone?: BMI is a population screening tool. It does not measure body fat directly and may misclassify muscular or elderly individuals.
What is a healthy BMI?: For most adults, WHO classifies 18.5–24.9 as normal weight. See our healthy-range reference for full categories.

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