BMI Calculator
Enter your height and weight to get your BMI, your category and the healthy weight range for your height.
Quick answer
BMI = weight in kg ÷ (height in metres)². In pounds and inches, BMI = 703 × weight ÷ height². For adults, under 18.5 is underweight, 18.5–24.9 is a healthy weight, 25–29.9 is overweight and 30 or more is obese. Someone 175 cm tall weighing 70 kg has a BMI of 22.9 (healthy weight).
Your BMI
22.9
- Category
- Healthy weight
- Healthy weight for your height
- 56.7 – 76.3 kg
WHO adult categories. BMI does not measure body fat directly — talk to a doctor about your health.
Healthy weight range by height (BMI 18.5–24.9)
| Height | Healthy weight (kg) | Healthy weight (lb) |
|---|---|---|
| 150 cm (4′11″) | 42 – 56 kg | 92 – 124 lb |
| 155 cm (5′1″) | 44 – 60 kg | 98 – 132 lb |
| 160 cm (5′3″) | 47 – 64 kg | 104 – 141 lb |
| 165 cm (5′5″) | 50 – 68 kg | 111 – 149 lb |
| 170 cm (5′7″) | 53 – 72 kg | 118 – 159 lb |
| 175 cm (5′9″) | 57 – 76 kg | 125 – 168 lb |
| 180 cm (5′11″) | 60 – 81 kg | 132 – 178 lb |
| 185 cm (6′1″) | 63 – 85 kg | 140 – 188 lb |
| 190 cm (6′3″) | 67 – 90 kg | 147 – 198 lb |
How it works
Body mass index compares your weight with your height. It is calculated as weight in kilograms divided by height in metres squared — or, in US units, 703 times weight in pounds divided by height in inches squared. Doctors use it as a quick screening number because it needs no equipment and correlates reasonably well with body fat across large groups of people.
The World Health Organization's adult categories are: below 18.5 underweight, 18.5 to 24.9 healthy, 25 to 29.9 overweight, and 30 or above obese (with 35 and 40 marking higher classes). Some health bodies use lower cut-offs for people of South Asian, Chinese and other Asian backgrounds — overweight from 23 and obese from 27.5 — because health risks rise at a lower BMI.
BMI has limits. It cannot tell muscle from fat, so athletes may score as overweight, and it says nothing about where fat is stored. Waist size is a useful second check: a waist over half your height is a sign of raised health risk. BMI categories here are for adults; children and teenagers are assessed with age- and sex-specific percentiles.
Frequently asked questions
What is a healthy BMI?
For most adults, 18.5 to 24.9. Some guidelines use 18.5 to 22.9 for people of Asian descent.
How do I calculate BMI in pounds?
Multiply your weight in pounds by 703, then divide by your height in inches squared. For 160 lb at 5′9″ (69 in): 703 × 160 ÷ 4,761 = 23.6.
Is BMI accurate for muscular people?
Not always. Muscle weighs more than fat, so people with a lot of muscle can have a high BMI while carrying little body fat.