BMI Calculator | Body Mass Index Tool - CalcHub
Free BMI calculator. Calculate your Body Mass Index using height and weight. Get health category and recommended ranges. Supports metric and imperial.
BMI Categories
| Category | BMI Range |
|---|---|
| Underweight | < 18.5 |
| Normal weight | 18.5 – 25 |
| Overweight | 25 – 30 |
| Obese (Class I) | 30 – 35 |
| Obese (Class II) | 35 – 40 |
| Obese (Class III) | 40+ |
What is BMI Calculator?
How to Use BMI Calculator
Select your preferred unit system (metric or imperial). Enter your height and weight. The calculator instantly displays your BMI value, health category, and a color-coded scale showing where you fall. It also shows the healthy weight range for your height.
How BMI Calculator Works
Common Use Cases
- Checking your BMI as part of a health assessment
- Tracking weight management progress over time
- Understanding which weight category you fall into
- Determining a healthy weight range for your height
- Screening tool before discussing weight with a healthcare provider
Frequently Asked Questions
What is a normal BMI range?▼
A normal (healthy) BMI is between 18.5 and 24.9. A BMI below 18.5 is considered underweight, 25.0-29.9 is overweight, and 30.0 or above is obese.
Is BMI accurate for everyone?▼
BMI is a useful screening tool but has limitations. It does not account for muscle mass, bone density, age, sex, or body composition. Athletes with high muscle mass may have a high BMI despite being healthy. Always consult a healthcare professional for a comprehensive assessment.
How is BMI calculated?▼
BMI = weight (kg) / height (m)^2. For imperial units: BMI = (weight (lbs) / height (in)^2) * 703.
What BMI is considered obese?▼
A BMI of 30.0 or higher is classified as obese. Obesity is further divided into Class I (30-34.9), Class II (35-39.9), and Class III (40+).