Body Mass Index
A quick population-level health screening metric. Useful for general adults, less so for muscular individuals, athletes, or specific populations.
Your BMI
25.8
Slightly overweight
Under
<18.5
Normal
18.5–24.9
Over
25–29.9
Obese
≥30
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What BMI tells you
BMI = weight(kg) / height(m)². It's a quick population-level health screening metric — useful for tracking trends, making rough categorizations, and flagging risk.
What BMI doesn't tell you
- Muscle vs fat: athletes and lifters often classify as "overweight" or "obese" by BMI while having excellent body composition
- Fat distribution: visceral fat (belly) is more dangerous than subcutaneous (everywhere else); BMI doesn't distinguish
- Age: ideal BMI shifts slightly upward with age; older adults can be healthier at BMI 25-27 than 22
- Ethnicity: health risks at given BMI vary across populations (Asian populations face risks at lower BMI; African-Americans at higher)
Better metrics
Waist circumference, waist-to-height ratio, and body fat % all give better individual signals than BMI. For lifters specifically, waist measurement and progress photos beat BMI by a wide margin.