BMI / IMC Calculator
Use this index masa corporal calculator to estimate your body mass index using metric or imperial units.
This tool is for educational purposes and does not replace professional medical advice.
What is the index masa corporal (IMC/BMI)?
The índice de masa corporal (IMC), known in English as Body Mass Index (BMI), is a simple screening value that compares your weight with your height. It helps estimate whether your weight is in a range commonly associated with better health outcomes. While it is not a diagnosis, it is often used by clinicians, coaches, and public health organizations as a quick first check.
BMI is popular because it is fast, low-cost, and easy to calculate. You only need two inputs: height and weight. This calculator does the math for you and also shows an interpretation category.
How to use this calculator
Step-by-step
- Select your preferred unit system: metric or imperial.
- Enter your height and weight values.
- Click Calculate to see your BMI result and category.
- Review the healthy weight range estimate for your height.
BMI formulas
Metric formula
BMI = weight (kg) / [height (m)]²
Imperial formula
BMI = 703 × weight (lb) / [height (in)]²
BMI categories (adults)
| Category | BMI Range |
|---|---|
| Underweight | Less than 18.5 |
| Normal weight | 18.5 to 24.9 |
| Overweight | 25.0 to 29.9 |
| Obesity (Class I) | 30.0 to 34.9 |
| Obesity (Class II) | 35.0 to 39.9 |
| Obesity (Class III) | 40.0 and above |
Why BMI is useful—and why it has limits
Useful because:
- It is easy and quick for large populations.
- It can flag possible risk and motivate early action.
- It gives a common language for health conversations.
Limitations to understand:
- BMI does not directly measure body fat percentage.
- It cannot distinguish muscle mass from fat mass.
- It does not account for fat distribution (for example, abdominal fat).
- Age, sex, ethnicity, and athletic status can affect interpretation.
Because of these limits, BMI works best when combined with additional indicators such as waist circumference, blood pressure, fasting glucose, lipids, physical activity level, and overall lifestyle patterns.
Healthy next steps after calculating your BMI
- Track trends over weeks and months instead of focusing on one reading.
- Pair BMI with waist measurements for better context.
- Prioritize nutrition quality, sleep, stress management, and regular movement.
- Discuss your results with a healthcare professional if you have concerns.
Frequently asked questions
Is BMI accurate for athletes?
Sometimes not. Athletes with higher muscle mass may show elevated BMI despite low body fat. In these cases, body composition tests provide a clearer picture.
Can BMI be used for children?
Children and teens are evaluated using age- and sex-specific BMI percentiles, not the adult category table above.
How often should I check BMI?
Monthly or every few weeks is usually enough for trend tracking. Daily checks are rarely necessary and can be misleading.
Final takeaway
This index masa corporal calculator gives you a fast, practical BMI estimate and category. Use it as a starting point, not a final diagnosis. Sustainable health is built through consistent habits, thoughtful monitoring, and professional guidance when needed.