BMI Calculator
Calculate your Body Mass Index (BMI) with precision. Use this tool to determine if your weight is healthy based on your height, weight, age, and sex.
BMI Calculator
About the BMI Calculator
The Body Mass Index (BMI) is a measure that uses your height and weight to determine if your weight is healthy. It is calculated using the formula:
BMI = weight (kg) / [height (m)]²
For more information, visit the Wikipedia page on BMI.
How Age and Sex Affect BMI
Age and sex are important factors when interpreting BMI. For children and adolescents, BMI is compared to percentiles based on age and sex. For adults, BMI categories are standard. For older adults, BMI may need to be interpreted differently due to changes in muscle mass and bone density.
BMI Categories
- Underweight: BMI less than 18.5
- Normal weight: BMI between 18.5 and 24.9
- Overweight: BMI between 25 and 29.9
- Obese: BMI 30 or greater
BMI Table
| Category | BMI (kg/m²) | BMI Prime |
|---|---|---|
| Underweight (Severe thinness) | < 16.0 | < 0.64 |
| Underweight (Moderate thinness) | 16.0–17.0 | 0.64–0.68 |
| Underweight (Mild thinness) | 17.0–18.5 | 0.68–0.74 |
| Normal range | 18.5–25.0 | 0.74–1.00 |
| Overweight (Pre-obese) | 25.0–30.0 | 1.00–1.20 |
| Obese (Class I) | 30.0–35.0 | 1.20–1.40 |
| Obese (Class II) | 35.0–40.0 | 1.40–1.60 |
| Obese (Class III) | ≥ 40.0 | ≥ 1.60 |
Source: Wikipedia - BMI Categories
Frequently Asked Questions
What is Body Mass Index (BMI)?
Body Mass Index (BMI) is a measure of body fat based on your weight in relation to your height. It is used to determine if you are underweight, normal weight, overweight, or obese. Use our BMI Calculator to find your BMI and explore tools like the BMI chart and healthy weight calculator.
How does the BMI Calculator work for women?
The BMI Calculator works the same for men and women, but women may have different body fat percentages at the same BMI. Use our BMI calculator for women to determine your BMI and compare it to the BMI chart for women.
Can I use the BMI Calculator for children?
Yes, our pediatric BMI calculator is designed to calculate BMI for children and adolescents. It uses age and sex-specific percentiles to interpret the results.
What is a healthy BMI for weight loss?
A healthy BMI is typically between 18.5 and 24.9. Use our BMI calculator for weight loss to track your progress and achieve your ideal weight.
What is the BMI scale?
The BMI scale categorizes BMI into underweight, normal weight, overweight, and obese. Check our BMI chart for detailed ranges and BMI Prime values.
Need Help with Calculations or Custom Tools?
If you need assistance with using our calculators, have questions about specific calculations, or require a custom calculation tool tailored to your needs, feel free to reach out. We're here to support you!