BMI calculator
This BMI calculator gives you body mass index and the weight range that corresponds to a "healthy" BMI for your height. It also comes with a warning most BMI pages leave out: if you lift, this number is probably wrong about you.
An estimate for training decisions — not medical advice.
BMI categories
The World Health Organization bands for adults.
| Category | BMI |
|---|---|
| Underweight | < 18.5 |
| Healthy weight | 18.5 – 24.9 |
| Overweight | 25 – 29.9 |
| Obese | ≥ 30.0 |
What BMI actually measures
BMI is weight divided by height squared. That's it. It was designed in the 19th century to describe populations, and at that job it's genuinely useful — it predicts health outcomes well across large groups.
Applied to one person it has no idea what that weight is made of. A 95 kg lifter at 180 cm and a sedentary 95 kg person at 180 cm get the same BMI of 29.3, and the number is meaningful for exactly one of them.
Better numbers for a lifter
If you train, three measures beat BMI. Waist circumference tracks the fat that actually matters. Body fat percentage — even a rough tape estimate from our body fat calculator — separates muscle from fat. And your training log: weight climbing while your lifts climb is a very different situation from weight climbing while they stall.
Tanko syncs body weight and body fat with Apple Health and charts them next to your training, which is the only context that makes bodyweight numbers readable.
Frequently asked questions
Is BMI accurate for muscular people?
No. BMI can't distinguish muscle from fat, so trained lifters routinely score "overweight" while carrying low body fat.
What is a healthy BMI?
18.5 to 24.9 for adults, per the WHO. The calculator above converts that band into an actual weight range for your height.
Should I ignore BMI completely?
Not completely — if you don't train and your BMI is well above 30, that's worth acting on. Just don't let it override what a tape measure and your training log tell you.
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