BMI Calculator | Body Mass Index for Adults, Teens & Seniors

Free, accurate BMI calculator for all age groups - calculate standard/metric BMI, healthy weight range, BMI prime, waist-to-height ratio (WHtR), and calorie targets tailored to your age and activity level.

Quick Jump to BMI Tools

Adult BMI (Standard) Adult BMI (Metric) Teen BMI (Age-Adjusted) Senior BMI (65+) Athlete BMI (Muscle-Adjusted) Healthy Weight Range BMI Prime Waist-to-Height Ratio (WHtR) TDEE Calorie Target BMI to Body Fat % Estimate

1. Adult BMI Calculator (lbs / inches)

Calculate BMI for adults (18-64) using US standard units (pounds/inches) with official WHO categories.

2. Adult BMI Calculator (kg / cm)

International metric BMI calculator for adults - kilograms and centimeters (WHO-approved formula).

3. Teen BMI Calculator (10-17 Years)

Age and gender-adjusted BMI for teenagers (CDC growth chart standards) - no generic adult formula.

4. Senior BMI Calculator (65+ Years)

BMI for seniors (65+) with adjusted healthy range (22-28) - accounts for age-related muscle loss.

5. Athlete BMI Calculator (Muscle-Adjusted)

Muscle-adjusted BMI for athletes/fitness enthusiasts - corrects standard BMI bias against high muscle mass.

6. Healthy Weight Range (By Height)

Age-adjusted healthy weight range based on height - no one-size-fits-all results.

7. BMI Prime Calculator

BMI Prime (BMI/25) - shows your BMI relative to the ideal 25 (1.0 = perfect, <0.74 = underweight, >1.2 = obese).

8. Waist-to-Height Ratio (WHtR)

Waist-to-Height Ratio (WHtR) - better than BMI for assessing visceral fat and metabolic disease risk (ideal <0.5).

9. TDEE Calorie Target (Age/Activity)

Total Daily Energy Expenditure (TDEE) - personalized calorie target for weight maintenance (age/activity adjusted).

10. BMI to Body Fat % Estimate

Gender-adjusted body fat percentage estimate from BMI - quick alternative to skinfold calipers.