# BMI Calculator

Calculate your Body Mass Index (BMI) instantly with our free calculator. Get your WHO classification and healthy weight range based on your height.

## What this calculates

Body Mass Index (BMI) is a simple measure of body fat based on your weight and height. Enter your measurements below to find out your BMI and see how it compares to the WHO classification standards.

## Inputs

- **Weight** (kg) — min 1, max 500
- **Height** (cm) — min 50, max 300

## Outputs

- **BMI** — Your Body Mass Index
- **WHO Classification** — formatted as text — Weight status category per WHO guidelines
- **Healthy Weight Range** — formatted as text — Weight range for a BMI of 18.5–24.9 at your height

## Details

BMI is calculated by dividing your weight in kilograms by the square of your height in meters: BMI = weight (kg) / height (m)². The World Health Organization (WHO) classifies BMI into several categories ranging from severe thinness (below 16) to obese class III (40 and above). A BMI between 18.5 and 24.9 is considered normal weight. While BMI is a useful screening tool, it does not directly measure body fat and may not account for factors such as muscle mass, bone density, age, and sex.

## Frequently Asked Questions

**Q: What is a healthy BMI range?**

A: According to the WHO, a healthy BMI is between 18.5 and 24.9 kg/m². Values below 18.5 indicate underweight, while values of 25 and above indicate overweight or obesity.

**Q: Is BMI accurate for everyone?**

A: BMI is a useful screening tool for the general population, but it has limitations. It does not distinguish between muscle and fat mass, so very muscular individuals may have a high BMI without excess body fat. Age, sex, ethnicity, and body composition also affect the interpretation of BMI.

**Q: Should I rely solely on BMI for health decisions?**

A: No. BMI is one of many indicators of health. You should consult a healthcare professional for a comprehensive assessment that considers BMI alongside other factors such as waist circumference, body fat percentage, blood pressure, and blood work.

**Q: How is BMI calculated?**

A: BMI is calculated by dividing your body weight in kilograms by the square of your height in meters. The formula is: BMI = weight (kg) / [height (m)]².

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Source: https://vastcalc.com/calculators/health/bmi
Category: Health & Fitness
Last updated: 2026-04-21