BMI calculator
Your body mass index, the WHO adult band and the healthy weight range for your height.
Options
175 and 1.75 both mean 175 cm.
Result
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Enter your height and weight to see the band.
WHO classification for adults
| Category | BMI |
|---|---|
| Underweight ▸ Your result | Under 18.5 |
| Normal weight ▸ Your result | 18.5 ≤ BMI < 25.0 |
| Overweight ▸ Your result | 25.0 ≤ BMI < 30.0 |
| Obesity class I ▸ Your result | 30.0 ≤ BMI < 35.0 |
| Obesity class II ▸ Your result | 35.0 ≤ BMI < 40.0 |
| Obesity class III ▸ Your result | 40.0 and over |
Bands from the World Health Organization adult classification. BMI is a screening number, not a diagnosis, and it does not account for muscle mass, pregnancy, athletes or anyone under 18.
Related tools
Type your height and your weight and you get the body mass index, the band the World Health Organization uses for adults, and the weights that would put you in the normal band at your height. Switch between centimetres and kilograms and feet, inches and pounds: what you already typed is converted, not cleared. BMI is a screening number, not a diagnosis. It says nothing about muscle, and the adult bands do not fit pregnancy, athletes or anyone under 18. Ask a doctor what your figure means for you. Everything runs in your browser and nothing is uploaded.
How to use
- Choose metric or imperial units.
- Type your height. In metric, 175 and 1.75 both mean 175 cm.
- Type your weight in the field beside it.
- Read the index, the band it falls in and the healthy weight range for your height.
- Press Copy result to take the three figures with you.
What it handles
- Height accepts 175, 1.75 and 1,75, so a comma keyboard and a metre habit both work.
- The category uses the unrounded result. The displayed BMI is rounded to one decimal, so a value just below 25 may display as 25.0 while remaining below that boundary.
- Switching units converts what is in the fields with the exact factors, 1 inch = 2.54 cm and 1 pound = 0.45359237 kg, so switching back gives the same numbers.
- The healthy weight range is rounded inwards, so every weight between the two figures really does read as a normal BMI.
- A height outside 50 cm to 275 cm, or a weight outside 2 kg to 650 kg, gets a line under the field instead of a nonsense index.
- Fields are only marked when you leave them, so 1 on the way to 175 is never called a mistake.
FAQ
What counts as a healthy BMI?
The World Health Organization puts adults from 18.5 to 24.9 in the normal weight band, under 18.5 in underweight, 25 to 29.9 in overweight, and 30 and above in obesity, split into three classes at 30, 35 and 40. The table on this page marks the band your figure lands in.
Is BMI accurate for everyone?
No. It compares weight with height and knows nothing else about you. A muscular athlete can read as overweight while carrying very little fat. The classification is for adults: it does not apply during pregnancy, or to anyone under 18, who is measured against growth charts instead.
How do I calculate BMI by hand?
Divide your weight in kilograms by your height in metres multiplied by itself. Someone 1.75 m tall weighing 70 kg has 70 divided by 3.0625, which is 22.9. With pounds and inches, divide weight by height squared and multiply by 703. This page converts imperial values and uses the metric formula.
Is my height and weight uploaded anywhere?
No. The calculation happens in the page you have already loaded, so nothing is sent to a server and nothing is logged. Your last measurements stay in this browser so the page opens where you left it, and Clear removes them. The link keeps the values, so share it carefully.
What should I do about my result?
Treat it as a screening number, not a verdict. If it sits outside the normal band, or sits inside it and you still have concerns, talk to a doctor, who can look at more than one ratio. This page gives no medical advice and cannot replace that conversation.
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