Calculate your Body Mass Index (BMI) using metric or US units. Get your BMI category, healthy weight range, and reference tables.
Tip: BMI is a screening tool and does not directly measure body fat. Always consult a clinician for medical advice.
| BMI Range | Category | General Health Risk (Typical) |
|---|---|---|
| Below 18.5 | Underweight | Possible nutritional deficiency |
| 18.5 – 24.9 | Normal Weight | Low risk |
| 25.0 – 29.9 | Overweight | Moderate risk |
| 30.0 – 34.9 | Obesity Class I | High risk |
| 35.0 – 39.9 | Obesity Class II | Very high risk |
| 40.0 and above | Obesity Class III (Severe) | Extremely high risk |
This table helps you estimate BMI quickly. Pick a height row and weight column. (This sample is in cm + kg.)
BMI (Body Mass Index) is a number calculated from your height and weight. It is used as a simple screening method to categorize weight status in adults.
Metric: BMI = weight (kg) / height² (m²)
US: BMI = (weight (lb) / height² (in²)) × 703
Your “healthy weight range” is calculated using the normal BMI range (18.5–24.9):
BMI does not directly measure body fat and may overestimate fat in athletes or underestimate fat in older adults. Consider other measures such as waist circumference, body fat percentage, or medical assessment when needed.
A healthy BMI range for most adults is between 18.5 and 24.9.
A BMI between 25.0 and 29.9 is typically classified as overweight.
A BMI of 30.0 or higher is typically classified as obesity.
BMI is a useful screening tool but it doesn’t directly measure body fat. Muscle mass, age, and other factors can affect BMI interpretation.
For adults, BMI categories are generally the same. However, children/teens use BMI-for-age percentiles. For adults, age and gender can influence body composition, so BMI should be interpreted along with other health indicators.