BMI & Waist-to-Height Ratio Calculator

Body Mass Index (BMI) is a widely used screening tool that estimates body fat based on height and weight. Developed by Belgian mathematician Adolphe Quetelet in 1835, BMI provides a quick assessment of whether a person falls into a healthy weight range. The Navy body fat percentage calculator offers a more accurate assessment of body composition for athletes and fitness enthusiasts.

BMI Formula

BMI Categories

Based on WHO classifications:

The Waist-to-Height Ratio (WHtR) is increasingly recognized as a better predictor of health risks than BMI alone. This metric assesses abdominal obesity, which is more strongly linked to cardiovascular disease and metabolic disorders than overall body weight.

WHtR Formula

WHtR Guidelines

• Below 0.4: Extremely slim (may indicate underweight)
• 0.4 - 0.5: Healthy range with low health risks
• 0.5 - 0.6: Overweight with increased health risks
• Above 0.6: Highly overweight with significantly increased health risks

Research shows that waist-to-height ratio is a superior predictor of cardiovascular risk compared to BMI alone (Browning, Hsieh, & Ashwell, 2010). For optimal health outcomes, consider using this metric alongside our body fat percentage calculator for a comprehensive assessment.

BMI Limitations

• Does not distinguish between muscle mass and fat mass
• May not be accurate for athletes with high muscle mass
• Different ethnic groups may have different health risk thresholds
• Not suitable for pregnant women, children, or elderly individuals
• Does not account for fat distribution patterns

When to Consult a Healthcare Professional

• BMI results fall outside the normal range
• You have concerns about your weight or health
• You're planning significant dietary or exercise changes
• You have existing health conditions
• For personalized health assessment and recommendations

1. Quetelet, A. (1835). Sur l'homme et le développement de ses facultés, ou Essai de physique sociale. Bachelier, Paris.
2. World Health Organization. (2000). Obesity: preventing and managing the global epidemic. WHO Technical Report Series, 894.
3. Ashwell, M., Gunn, P., & Gibson, S. (2012). Waist‐to‐height ratio is a better screening tool than waist circumference and BMI for adult cardiometabolic risk factors: systematic review and meta‐analysis. Obesity Reviews, 13(3), 275-286.
4. Browning, L. M., Hsieh, S. D., & Ashwell, M. (2010). A systematic review of waist‐to‐height ratio as a screening tool for the prediction of cardiovascular disease and diabetes: 0·5 could be a suitable global boundary value. Nutrition Research Reviews, 23(2), 247-269.
5. Centers for Disease Control and Prevention. (2022). About Adult BMI. CDC website.