BMI Calculator
Enter your height and weight to calculate your body mass index (BMI) and see which standard adult category it falls into.
Last updated November 2, 2026
Result
BMI 23.5 (Normal weight)
| Measure | Value |
|---|---|
| BMI | 23.5 |
| Adult category | Normal weight |
| Weight for BMI 18.5 to 24.9 | 118.1 lb to 159 lb |
| Category | BMI |
|---|---|
| Underweight | below 18.5 |
| Normal weight | 18.5 to 24.9 |
| Overweight | 25 to 29.9 |
| Obesity | 30 and above |
BMI is a screening number for adults 18 and over. It does not measure body fat, muscle, age, sex or health, and it is not a diagnosis. General estimate only, not medical advice. Talk to a qualified health professional about your own situation.
Show the work
Formula: BMI = weight (kg) ÷ height (m)².
- You entered 5 ft 7 in, 150 lb. The formulas use 170.2 cm and 68 kg.
- Height in meters: 170.2 / 100 = 1.7018 m, squared = 2.8961.
- BMI = 68 ÷ 2.8961 = 23.5, which falls in the Normal weight band.
- Weight for BMI 18.5 to 24.9: 18.5 × 2.8961 = 118.1 lb and 24.9 × 2.8961 = 159 lb.
Result: BMI 23.5 (Normal weight)
How BMI is calculated
BMI = weight (kg) ÷ height (m)² = 703 × weight (lb) ÷ height (in)²
BMI is your weight in kilograms divided by your height in meters squared. A person who is 1.70 m tall and weighs 68 kg has a BMI of 68 ÷ 2.89 = 23.5. The adult categories are underweight below 18.5, normal weight 18.5 to 24.9, overweight 25 to 29.9 and obesity 30 and above.
BMI is a screening number, not a diagnosis. It does not separate muscle from fat, and the same BMI can mean different things for different body types, ages and ethnic backgrounds. It applies to adults 18 and over; children and teens are assessed with age-specific growth charts.
See how we calculate for the formulas, sources and review schedule behind every calculator.
This is an estimate, not medical advice
This calculator gives a general estimate from the published methods listed under Sources. It does not diagnose anything or replace advice from a doctor, dietitian or other qualified health professional, and individual needs differ. This page has not been reviewed by a medical professional.
BMI for Men and Women
The standard adult BMI formula is the same for men and women: weight in kilograms divided by height in meters squared. The CDC applies the same adult categories regardless of sex, so there is no separate BMI calculator for men or for women, and this one does not ask for sex. A woman and a man with the same height and weight get the same BMI and the same category.
BMI has limits for everyone. It uses only height and weight, so it cannot tell muscle from fat, show where fat is carried or measure fitness, and two people with the same BMI can have different body composition. Use it as one screening number and talk to a doctor or other health professional about what it means for you.
Sources
Official and primary sources for the statements on this page. Their authors have not reviewed or endorsed this page.
- Centers for Disease Control and Prevention, Adult BMI Categories (page dated March 19, 2024). Defines BMI as weight in kilograms divided by height in meters squared and lists the adult categories used here: under 18.5, 18.5 to under 25, 25 to under 30, and 30 or more
BMI is a screening number. It does not measure body fat or health, and the cut-offs do not fit every person, for example children, pregnant people or very muscular adults.
How to use the BMI Calculator
- Choose US or metric units.
- Enter your height and weight.
- Read your BMI, category and the weight range for a BMI of 18.5 to 24.9, then use Copy, Print or Share.
Worked example
A person who is 5 ft 7 in (1.702 m) and weighs 150 lb (68.0 kg) has BMI = 68.04 ÷ 1.702² = 23.5, which is in the normal weight range. A BMI of 18.5 to 24.9 at that height corresponds to about 118 to 159 lb.
| Category | BMI |
|---|---|
| Underweight | below 18.5 |
| Normal weight | 18.5 to 24.9 |
| Overweight | 25 to 29.9 |
| Obesity | 30 and above |
Frequently asked questions
What is a healthy BMI?
The standard adult range labelled normal weight is 18.5 to 24.9, but BMI alone cannot say whether you are healthy.
Is BMI accurate for athletes?
Not always. Muscle weighs more than fat, so muscular people can have a high BMI without excess body fat.
Does BMI work for children?
No. Children and teens use percentile charts that account for age and sex.
What should I do with my result?
Treat it as one screening number and talk to a doctor if you have concerns about your weight or health.
Are my numbers stored or sent anywhere?
No. The calculation runs in your browser and nothing you enter is saved or uploaded.