Calculate your Body Mass Index and learn about healthy weight ranges
Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, overweight, and obesity in adults. It is defined as a person's weight in kilograms divided by the square of their height in meters (kg/m²).
While BMI is not a direct measure of body fat, it is a useful screening tool to identify potential weight problems. Use our calculator to determine your BMI and understand what it means for your health.
BMI values are grouped into categories that indicate your weight status and potential health risks:
| BMI | Category | Health Risk |
|---|---|---|
| Below 18.5 | Underweight | Increased risk of nutritional deficiencies and osteoporosis |
| 18.5 - 24.9 | Normal weight | Lowest health risk |
| 25.0 - 29.9 | Overweight | Moderate risk of developing health problems |
| 30.0 and above | Obese | High risk of developing health problems like heart disease and diabetes |
Calculating your BMI is straightforward. You can use the formula:
For those using imperial measurements:
Our calculator above does all the math for you. Simply enter your height and weight, and we'll calculate your BMI instantly.
For a woman who is 5 feet 4 inches tall (163 cm), the healthy weight range based on BMI is:
This means a 5'4" female should ideally weigh between 108 and 145 pounds to be considered in the healthy BMI range. However, individual factors like muscle mass, body composition, and frame size can affect what weight is healthiest for a specific person.
A BMI of 20 falls within the normal weight category (18.5-24.9), which is generally considered healthy. While there's no single "perfect" BMI for everyone, values between 20-22 are often associated with the lowest health risks for most people.
However, it's important to remember that BMI is just one indicator of health. Other factors like body composition, distribution of fat, fitness level, and overall lifestyle play significant roles in determining your health status.
The "correct" or healthy BMI range for adults is generally considered to be between 18.5 and 24.9. This range is associated with the lowest risk of health problems related to weight.
It's important to note that:
BMI is a useful screening tool for weight categories, but it has limitations as a comprehensive health indicator:
Advantages of BMI:
Limitations of BMI:
For a more complete health assessment, BMI should be considered alongside other measurements like waist circumference, body fat percentage, blood pressure, cholesterol levels, and lifestyle factors.
While some critics argue that BMI is an outdated measurement, it remains widely used in healthcare and research because:
However, many health professionals now recommend using BMI in combination with other assessments for a more complete picture of health. Measurements like waist-to-hip ratio, body fat percentage, and metabolic health markers provide additional insights that BMI alone cannot offer.
Rather than being completely outdated, BMI is best viewed as a starting point for health assessments rather than a definitive diagnosis tool.