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BMI Calculator — Know Your Body Mass Index in Seconds
BMI Calculator helps you calculate your Body Mass Index using height and weight — in metric (kg/cm) or imperial (lbs/in). Get your BMI value, weight category, and personalized health insights — instantly and for free.
Your BMI is within the healthy range (18.5–24.9).
• Eat balanced meals with fruits, vegetables, and lean protein
• Aim for 150 mins of moderate exercise per week
• Prioritize 7–9 hours of sleep nightly
BMI Calculator: What Is Body Mass Index?
BMI (Body Mass Index) is a simple screening tool that estimates body fat based on height and weight. While not a direct measure of body fat, it’s widely used by healthcare professionals to assess weight-related health risks. Our BMI Calculator follows WHO and CDC standards.
How to Calculate BMI
The formula is the same worldwide — only units change:
- Metric: BMI = weight (kg) ÷ [height (m)]²
- Imperial: BMI = [weight (lbs) ÷ height (in)²] × 703
Example: 70 kg, 175 cm → 1.75 m → 70 ÷ (1.75 × 1.75) = 70 ÷ 3.0625 = 22.9
WHO BMI Classification Table
| BMI Range | Category | Health Risk |
|---|---|---|
| < 18.5 | Underweight | Increased risk of malnutrition |
| 18.5 – 24.9 | Normal weight | Lowest risk |
| 25.0 – 29.9 | Overweight | Increased risk of heart disease, diabetes |
| ≥ 30.0 | Obese | High risk of chronic conditions |
Source: World Health Organization (WHO)
Limitations of BMI
While useful, BMI has limitations — and our BMI Calculator is transparent about them:
- 💪 Muscle vs. Fat: Athletes may have high BMI due to muscle, not fat
- 👵 Age & Gender: Older adults may have higher fat % at same BMI
- 👶 Children: Use age- and sex-specific percentiles (CDC growth charts)
For better accuracy, combine BMI with waist circumference or body fat %.
More Free Health & Wellness Tools
Take control of your health with:
- Age Calculator — track your biological age
- Percentage Calculator — for nutrition labels & macros
- Water Intake Calculator — (coming soon)
Frequently Asked Questions
Q: What’s the ideal BMI for my age?
A: For adults (20+), the healthy range is 18.5–24.9 regardless of age. For children/teens, use CDC’s BMI-for-age charts.
Q: Can I use BMI during pregnancy?
A: No. BMI is not recommended during pregnancy. Weight gain guidelines are based on pre-pregnancy BMI — consult your doctor.
Q: Does this BMI Calculator store my data?
A: Absolutely not. All calculations happen in your browser — no data is sent, stored, or tracked.
