BMI Calculator for Men and Women

The BMI formula is the same for men and women: weight in kilograms divided by height in meters squared (kg/m²). The categories are also the same: underweight (<18.5), normal (18.5-24.9), overweight (25-29.9), obese (30+).

However, men and women with the same BMI may have different body compositions. Women naturally have more body fat than men at the same BMI. Men tend to have more muscle mass, which weighs more than fat.

This means BMI can overestimate body fat in athletic men (who have extra muscle) and underestimate body fat in women (who naturally carry more fat). BMI is a starting point, not a definitive measure.

For a more complete picture, combine BMI with waist circumference. A waist measurement over 40 inches (102 cm) for men or 35 inches (88 cm) for women indicates higher health risk, regardless of BMI.

Underweight (BMI below 18.5): May indicate insufficient nutrition, eating disorders, or underlying health conditions. Consult a doctor if you're in this range.

Normal weight (BMI 18.5-24.9): Generally considered the healthiest range. Lowest risk of weight-related health problems.

Overweight (BMI 25-29.9): Increased risk of heart disease, type 2 diabetes, and high blood pressure. Lifestyle changes (diet, exercise) can help move into the normal range.

Obese (BMI 30+): Significantly increased risk of weight-related health conditions. Medical guidance is recommended for weight management.

These categories are defined by the World Health Organization (WHO) and apply to adults aged 20 and over. Children and teens use age-specific BMI percentiles instead.

Open the BMI Calculator tool in your browser. No installation or signup required.

Choose your preferred unit system: Metric (cm/kg) or Imperial (ft·in/lb).

Enter your height and weight. The calculator instantly shows your BMI value and category.

The healthy weight range for your height is also displayed, showing what weights correspond to a BMI of 18.5-24.9 for your height.

Use the copy button to copy your BMI result if you want to share it with your doctor or track it over time.

BMI doesn't account for muscle mass. Athletes and bodybuilders may have a high BMI but low body fat. A 6-foot, 220-pound football player might have a BMI of 28 (overweight) but only 12% body fat.

BMI doesn't account for body composition. Two people with the same BMI can have very different amounts of body fat vs muscle. Women naturally have more body fat than men at the same BMI.

BMI doesn't account for age. Older adults may have a 'normal' BMI but high body fat and low muscle mass. Some studies suggest slightly higher BMI targets (25-27) may be healthier for older adults.

BMI doesn't account for fat distribution. Belly fat (visceral fat) is more dangerous than fat carried on the hips and thighs. Waist circumference is a better indicator of metabolic health risk.

Use BMI as one data point, not as a definitive health assessment. For a complete picture, combine it with waist circumference, body fat percentage, and a conversation with your healthcare provider.