BMI Calculator
Check your Body Mass Index in metric or imperial units, and see your healthy weight range.
BMI Formula
What BMI Doesn't Tell You
- Muscle vs fat composition
- Where fat is stored (visceral fat matters more than subcutaneous)
- Age and bone density
- Metabolic health markers like blood sugar, cholesterol
Use BMI as a starting point, not a final verdict.
Frequently Asked Questions
What is BMI?
Body Mass Index = weight (kg) ÷ height (m)². It's a quick screening indicator of whether someone has a healthy body weight for their height.
What is a healthy BMI?
WHO classification: Under 18.5 = underweight. 18.5–24.9 = normal. 25–29.9 = overweight. 30+ = obese. (Asians: slightly lower thresholds — 23+ overweight).
Is BMI accurate for athletes?
Not very. BMI doesn't distinguish muscle from fat, so muscular athletes may show as 'overweight.' Use body fat % for more accuracy.
Does BMI differ by gender?
The formula is the same, but healthy ranges can differ slightly. Women naturally have higher body fat %; men carry more muscle.
How often should I check my BMI?
Once a month is plenty. Daily fluctuations are water weight — focus on weekly or monthly trends.