Calculate your Body Mass Index (BMI) and understand your health category based on height and weight measurements
Enter your weight and height to calculate BMI
Body Mass Index (BMI) is a widely used measure to assess whether your weight is healthy for your height. Our BMI calculator provides instant results with color-coded health categories, helping you understand where you stand on the weight spectrum. While BMI is a useful screening tool, it's important to remember that it doesn't directly measure body fat or overall health, and should be considered alongside other health indicators.
To use the calculator, simply enter your weight in kilograms and your height in centimeters. Click "Calculate BMI" to instantly see your BMI value, health category (underweight, normal weight, overweight, or obese), and personalized health advice based on your result. The calculator uses the standard WHO BMI formula that's recognized globally by healthcare professionals.
This tool is useful for tracking weight management progress, setting fitness goals, understanding health risks associated with weight, and having informed discussions with healthcare providers. Regular BMI monitoring can help you maintain a healthy weight range, though it should be used as one of several health metrics rather than the sole indicator of health.
BMI is calculated using a simple mathematical formula that relates weight to height. The formula is internationally standardized and used by health organizations worldwide.
Example Calculation:
Weight = 70 kg, Height = 175 cm (1.75 m)
BMI = 70 ÷ (1.75 × 1.75) = 70 ÷ 3.0625 = 22.9
Result: Normal Weight (BMI 18.5-24.9)
BMI Categories (WHO Standards):
These categories provide general guidelines, but individual health assessment should consider factors like age, gender, muscle mass, bone density, and overall health conditions.
While BMI is a useful tool, it's important to understand its limitations and what your results mean in context:
BMI Limitations: BMI doesn't distinguish between muscle and fat mass. Athletes with high muscle mass may have high BMI but low body fat. Similarly, older adults may have normal BMI but high body fat percentage. BMI also doesn't account for body fat distribution, which affects health risks differently.
Health Implications: Both underweight and overweight categories are associated with increased health risks. Underweight may indicate malnutrition or underlying health conditions. Overweight and obesity are linked to increased risks of heart disease, diabetes, high blood pressure, certain cancers, and joint problems. However, being in the "normal" range doesn't guarantee good health.
Beyond BMI: Consider other health indicators like waist circumference, waist-to-hip ratio, body fat percentage, blood pressure, cholesterol levels, and fitness level. A comprehensive health assessment should include multiple factors. Consult healthcare professionals for personalized health evaluation and advice.
Age and Gender Considerations: BMI standards may not be equally applicable across all age groups and genders. Children and teens use age and gender-specific BMI percentiles. Pregnant women should not use standard BMI calculations. Ethnic backgrounds may also influence BMI interpretation, as body composition varies across populations.
BMI is a useful screening tool but not a direct measure of health or body fat. It works well for average populations but has limitations for athletes, bodybuilders, older adults, and certain ethnic groups. Use BMI as one indicator among many, including waist circumference, body composition, fitness level, and medical markers like blood pressure and cholesterol.
If your BMI is outside the normal range, consult a healthcare provider for a comprehensive health assessment. They can evaluate other health factors and recommend personalized strategies. For overweight/obesity, this typically includes balanced nutrition, regular physical activity, and behavioral changes. For underweight, they'll investigate underlying causes and develop appropriate interventions.
Improving BMI involves gradual, sustainable lifestyle changes. For weight loss: create a modest calorie deficit through balanced nutrition and increased physical activity, aim for 0.5-1 kg weight loss per week, include strength training to preserve muscle mass. For weight gain: increase calorie intake with nutrient-dense foods, include strength training to build muscle, address any underlying health conditions affecting weight.
Standard adult BMI calculations don't apply to children under 18 (who use age-specific percentiles), pregnant or breastfeeding women, athletes with high muscle mass, bodybuilders, frail or sedentary elderly individuals, or people with physical disabilities affecting stature. These groups need specialized assessments from healthcare professionals.
For general health monitoring, checking BMI monthly is sufficient. More frequent checking (weekly) may be appropriate during active weight management programs. Remember that weight naturally fluctuates daily due to water retention, food intake, and other factors. Focus on trends over time rather than daily variations. Combine BMI tracking with other health metrics for comprehensive monitoring.