Quickly check your body mass index (BMI) with the free BMI calculator and find out if you are underweight, normal, overweight or obese. Our fast, accurate and mobile-friendly calculator helps you accurately assess your health risks based on the WHO standard.
BMI Calculator
Calculate your Body Mass Index (BMI) to understand your weight category.
Find out your BMI
Enter your details to get started.
Your BMI Result
Healthy BMI range: 18.5 kg/m² - 25 kg/m²
By maintaining a healthy weight, you lower your risk of developing serious health problems.
How to Calculate BMI (Body Mass Index)
Our BMI calculator helps you calculate BMI easily and accurately using your weight and height. BMI tells you whether you are underweight, normal, overweight or obese based on your body size.
Using the Metric System
Formula: BMI = weight (kg) ÷ height (m) × height (m)
Example:
Weight: 75 kg
Height: 177 cm (1.77 m)
BMI = 75 ÷ (1.77 × 1.77) = 75 ÷ 3.13 = 23.96
Using the Imperial System
Formula: BMI = [weight (lb) ÷ (height (in) × height (in)] × 703
Example:
Weight: 160 lbs
Height: 5’8” (68 inches)
BMI = (160 ÷ (68 × 68)) × 703 = (160 ÷ 4624) × 703 = 24.3
BMI Categories
| BMI | Weight Status |
|---|---|
| Below 18.5 | Underweight |
| 18.5–24.9 | Normal weight |
| 25–29.9 | Overweight |
| 30–35 | Obese |
| Over 35 | Morbid obesity |
Note: The same categories apply for both females and males.
BMI for Children
BMI for children is calculated similarly, using age- and gender-specific percentile charts for interpretation.
Example: A 6-year-old girl's 25th percentile means she has a higher BMI than 25% of girls her age.
Health Risks Based on BMI
| Overweight (BMI > 25) | Underweight (BMI < 18.5) |
|---|---|
| Type 2 diabetes | Nutrient deficiencies (e.g., iron, vitamins) |
| Heart disease | Anemia & poor immunity |
| High LDL, low HDL cholesterol | Osteoporosis & delayed growth (children) |
| Stroke & high blood pressure | Hormonal imbalance & menstrual issues |
| Gallbladder disease | Malnutrition & possible eating disorders |
| Insulin resistance | - |
| Sleep apnea & osteoarthritis | - |
| Skin issues & hernias | - |
| Varicose veins & cataracts | - |
| Gout & stress incontinence | - |
| Certain cancers (e.g., breast, colon) | - |
| Depression & PCOS in women | - |
