❤️ Health Last tested2026-05-13
BMI Calculator in 2 seconds.
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Quick answer
A 170 cm tall person weighing 70 kg has a BMI of 24.2 — in the healthy range (18.5–24.9). Enter your numbers below to see where you fall.
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BMI Calculator
Your BMI
24.2
Category
Normal
You're in the healthy weight range. Keep it up.
Where you fall on the BMI scale
< 18.5
18.5 – 25
25 – 30
30+
YOU
UnderweightNormalOverweightObese
✨ Live · BMI is a screening tool, not a diagnosis · Consult a doctor for medical advice
📖 How to use
3 steps. 5 seconds.
1
Pick metric or imperial units (top-right toggle)
2
Enter your height and weight
3
See your BMI, category, and position on the WHO health scale
🧮 The math
It's just a ratio.
The formula
BMI = weight (kg) ÷ height² (m)
Imperial version: BMI = (weight in lbs × 703) ÷ height² (in inches). Both give identical results — units cancel out.
❓ FAQ
Common questions.
What is BMI?
BMI (Body Mass Index) is a number calculated from your weight and height. It is used as a quick screening tool to categorize weight status. The formula is: BMI = weight (kg) ÷ height² (m).
What are the BMI categories (WHO)?
Below 18.5 = Underweight. 18.5–24.9 = Normal/healthy. 25.0–29.9 = Overweight. 30.0 and above = Obese (with three sub-classes). These are WHO standard ranges for adults.
Is BMI accurate for everyone?
BMI is a screening tool, not a diagnosis. It doesn't distinguish muscle from fat. Athletes and bodybuilders often have BMI in the 'overweight' range despite low body fat. Pregnant women, children, and the elderly need different metrics.
Should I use BMI or body fat percentage?
For everyday use, BMI is fine — it correlates with health outcomes at a population level. For more precision, combine BMI with waist-to-hip ratio or body-fat % measurement.
What is a healthy BMI?
Generally 18.5 to 24.9 for adults. However, for South and East Asian populations, the WHO suggests 18.5 to 22.9 due to differences in body composition and disease risk.