BMI Calculator
Calculate body mass index with US or metric units and a color-coded classification scale.
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Inputs
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Your BMI
23.0
Normal weight
Estimates only. Not medical advice.
Category
Normal weight
Healthy BMI range
18.5 – 24.9
Weight for healthy BMI
129 – 174 lb
23.0
Normal weight
UnderNormalOverObesity
Balanced meals
30 min activity
Stay hydrated
7–8 hrs sleep
Screening only — not a medical diagnosis.
BMI classification (adult)
| Category | BMI range |
|---|---|
| Underweight | < 18.5 |
| Normal weight | 18.5 – 24.9 |
| Overweight | 25 – 29.9 |
| Obesity | ≥ 30 |
Screening only
BMI is a population screening measure, not a medical diagnosis. Muscle mass, age, and body composition also matter.
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How this calculator works
Calculate body mass index with US or metric units and a color-coded classification scale.
How is it calculated?
US: BMI = 703 × lb / in². Metric: BMI = kg / m². Healthy adult range is commonly cited as 18.5–24.9.
Example
5′10″ and 160 lb → BMI ≈ 23.0 (normal weight range).
Frequently asked questions
Is BMI a diagnosis?+
No. It is a screening number only and does not diagnose health conditions.
What is a healthy BMI range?+
For many adults, 18.5–24.9 is the commonly cited “normal weight” band. Individual needs vary.
Why might athletes score high?+
Higher muscle mass can raise BMI without indicating excess fat.