Calculadora de IMC
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
IMC = peso (kg) / altura² (m²)
About this calculator
The BMI Calculator computes the Body Mass Index, a value used to classify underweight, normal weight, overweight, or obesity. The calculation is simple: weight in kilograms divided by height in meters squared (BMI = weight / height²). This metric was developed by statistician Adolphe Quetelet in the 19th century and is widely adopted by the World Health Organization (WHO) as an initial health indicator related to body weight.
To use the calculator, enter your weight and height in the provided fields. The result will show your BMI and the corresponding category: below 18.5 (underweight), 18.5 to 24.9 (normal), 25 to 29.9 (overweight), and above 30 (obesity). It is important to note that BMI does not directly measure body fat but serves as a warning for potential health risks. For example, very muscular people may have a high BMI without excess fat.
When to use it? The calculator is useful for quick assessments in medical check-ups, monitoring weight loss or muscle gain programs, and for anyone wanting to track their weight practically. However, it does not replace a full clinical evaluation. Cautions: BMI is not suitable for growing children, pregnant women, elderly individuals, or high-performance athletes. In these cases, other measures such as waist circumference or bioimpedance are more appropriate.
Frequently asked questions
Is BMI reliable for all body types?
No. BMI does not distinguish between muscle and fat, so athletes or very muscular people may have a high BMI without being obese. It is also not accurate for elderly or pregnant women.
What is the difference between BMI and body fat percentage?
BMI is a ratio of weight to height, while body fat percentage directly measures the amount of fat in the body. BMI is more practical but less precise.
How to interpret BMI results for children?
For children, BMI must be interpreted using specific growth charts by age and sex. Use pediatric calculators or consult a doctor.
What should I do if my BMI indicates obesity?
Seek a doctor or nutritionist for a full evaluation. BMI is a warning, but treatment should consider other factors like eating habits and health history.