BMI Calculate
Calculate your Body Mass Index and see your health category. Works with both metric and imperial units.
Your Measurements
Your BMI
24.2
Normal Weight
BMI Scale
Healthy Weight Range
53.5
kg
72.0
kg
Your BMI is within the healthy range. Maintain your current lifestyle with balanced diet and exercise.
What is BMI?
BMI is a simple numerical value that relates your weight to your height. It's one of the most commonly used screening tools to identify whether a person has a healthy body weight for their height.
While not a direct measure of body fat, BMI correlates with more direct measures like underwater weighing and is a quick, inexpensive way to screen for weight categories.
How is BMI Calculated?
The formula for calculating BMI is:
For imperial units (pounds and inches):
Metric Example
For a person 1.75m tall weighing 70kg:
BMI = 70 ÷ (1.75)² = 22.9
Imperial Example
For a person 5'9" (69in) tall weighing 155lbs:
BMI = (155 × 703) ÷ (69)² = 22.9
BMI Categories
The World Health Organization (WHO) defines the following BMI categories for adults:
| Category | BMI Range | Health Risk |
|---|---|---|
| Severely Underweight | < 16.0 | Very High |
| Underweight | 16.0 – 18.4 | Moderate |
| Normal Weight | 18.5 – 24.9 | Low |
| Overweight | 25.0 – 29.9 | Increased |
| Obese Class I | 30.0 – 34.9 | High |
| Obese Class II | 35.0 – 39.9 | Very High |
| Obese Class III | ≥ 40.0 | Extremely High |
Limitations of BMI
Not for Everyone
BMI may not be accurate for:
- Athletes and bodybuilders
- Pregnant women
- Children under 18
- Elderly individuals
What It Doesn't Measure
BMI cannot distinguish between:
- Muscle vs. fat mass
- Body fat distribution
- Bone density
- Overall fitness level
For a complete health assessment, consult a healthcare professional who can evaluate additional factors like body composition, waist circumference, and overall health history.
Maintaining a Healthy Weight
If your BMI is outside the healthy range, consider these evidence-based approaches:
- 1Focus on balanced nutrition rather than extreme diets
- 2Aim for 150+ minutes of moderate exercise per week
- 3Get adequate sleep (7-9 hours for adults)
- 4Stay hydrated and limit sugary beverages
- 5Consider tracking your daily calorie intake
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Calculate your body fat percentage using multiple methods including the US Navy formula, RFM, and BMI estimation. See your body composition and category.