BMI Calculator
Enter your height and weight in metric or imperial units. You get your body mass index, the WHO category it falls in, and the weight range that corresponds to a BMI of 18.5 to 24.9 at your height.
Your BMI
24.2
Normal range
- Weight for BMI 18.5 to 24.9
- 53.5 to 72.0 kg
- Height
- 170 cm
Saved results stay in this browser only. Clearing your browser data removes them.
WHO adult BMI ranges
| Range | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 to 24.9 | Normal range |
| 25 to 29.9 | Overweight |
| 30 to 34.9 | Obesity class I |
| 35 to 39.9 | Obesity class II |
| 40 and above | Obesity class III |
- BMI compares weight with height. It does not measure body fat, muscle or where fat sits, so it can mislead for athletes, older adults and some ethnic groups, and it is not used the same way for children. An estimate from a published formula, not a medical assessment. For health decisions, talk to a doctor or a qualified professional.
What BMI is, and what it is not
BMI is weight in kilograms divided by height in metres squared. The World Health Organization uses it to group adults into underweight, normal range, overweight and obesity classes.
It is a quick screening number, not a diagnosis. It does not measure body fat, muscle or where fat sits, so it can mislead for athletes, older adults and some ethnic groups, and it is not used the same way for children.
If your BMI is outside the normal range, or you are unsure what it means for you, talk to a doctor.
The formula
BMI = weight (kg) ÷ height (m)². Pounds and inches are converted to kilograms and centimetres first.
Common questions
How do I calculate BMI?
Divide your weight in kilograms by the square of your height in metres. For 70 kg and 1.70 m, that is 70 ÷ 2.89 = 24.2.
What is a normal BMI?
The WHO adult normal range is 18.5 to 24.9. Below 18.5 is underweight, 25 to 29.9 overweight, and 30 and above is obesity.
Is BMI accurate?
It is a useful screening number for populations but not a precise measure for an individual, because it ignores muscle, bone and fat distribution.
Is this medical advice?
No. For health decisions, talk to a doctor.
Keep your notes and photos together
SparkyLive is a personal capture hub for receipts, contact notes and photo memories, so what you want to remember is in one place on your phone.
Try SparkyLive (opens in a new tab)