Free BMI Calculator
The Best BMI Calculator to Calculate Your Body Mass Index Instantly - Free & Accurate
BMI Calculator - Calculate Your Body Mass Index
Why Use Our BMI Calculator?
Our BMI calculator is the best free BMI calculator online. This advanced BMI calculator uses the WHO standard formula to calculate your Body Mass Index instantly. Use this BMI calculator for quick health screening and weight assessment.
Whether you're tracking weight loss, monitoring health, or planning fitness goals, this free BMI calculator provides accurate results with personalized recommendations. Our BMI calculator delivers instant BMI calculation with health risk assessment, ideal weight range, and actionable advice - completely free, no signup required.
Instant
Calculate BMI in seconds
Accurate
WHO standard formula
Personalized
Custom recommendations
What is BMI? Understanding Body Mass Index
BMI (Body Mass Index) is a simple calculation using height and weight to assess if you're at a healthy weight. Our BMI calculator uses the standard WHO formula to determine your body mass index. Use this BMI calculator for quick health screening.
Normal Weight
BMI 18.5-24.9. This BMI calculator shows you're at healthy weight with low health risks.
Overweight
BMI 25-29.9. Our BMI calculator indicates moderate health risk. Weight loss recommended.
Obese
BMI 30+. This BMI calculator shows high health risk. Medical consultation advised.
How to Use This BMI Calculator
Our BMI calculator is the easiest way to check your body mass index. Follow these simple steps with this free BMI calculator:
Enter Your Weight
Input your current weight in kg or lbs. This BMI calculator accepts both metric and imperial units.
Enter Your Height
Input your height in cm or inches. The BMI calculator will automatically convert units for accurate results.
Optional: Add Age & Gender
For personalized recommendations, add your age and gender. This BMI calculator provides tailored advice.
Get Instant Results
The BMI calculator shows your BMI, category, health risk, ideal weight range, and personalized recommendations instantly.
BMI Categories Explained
Our BMI calculator uses WHO (World Health Organization) standards. This BMI calculator categorizes results as follows:
Severe Underweight
BMI < 16Health Risk: High - This BMI calculator result indicates severe malnutrition risk.
Immediate medical attention needed. The BMI calculator shows critically low body mass.
Underweight
BMI 16-18.4Health Risk: Moderate - This BMI calculator shows below healthy range.
Gradual weight gain recommended. Use this BMI calculator to track progress.
Normal Weight
BMI 18.5-24.9Health Risk: Low - This BMI calculator confirms healthy weight! ✅
Maintain current lifestyle. Use this BMI calculator periodically to monitor.
Overweight
BMI 25-29.9Health Risk: Moderate - This BMI calculator suggests weight loss.
Aim for 5-10% weight loss. Use this BMI calculator with our calorie deficit calculator.
Obese Class I
BMI 30-34.9Health Risk: High - This BMI calculator indicates obesity.
Medical consultation recommended. This BMI calculator can track your weight loss journey.
Obese Class II & III
BMI 35+Health Risk: Very High to Extreme - This BMI calculator shows severe obesity.
Immediate medical intervention needed. This BMI calculator should be used with professional guidance.
How Does This BMI Calculator Work?
BMI Formula
Our BMI calculator uses this standard formula. This BMI calculator automatically converts imperial units to metric for accurate calculation.
Example (Metric)
Weight: 70 kg, Height: 1.75 m
BMI = 70 ÷ (1.75 × 1.75)
BMI = 22.9 (Normal)
This BMI calculator would show "Normal Weight"
Example (Imperial)
Weight: 154 lbs, Height: 69 in
Convert: 70 kg, 1.75 m
BMI = 22.9 (Normal)
This BMI calculator handles conversion automatically
BMI Calculator Limitations
While our BMI calculator is useful, it has limitations. This BMI calculator doesn't measure body composition:
Doesn't Distinguish Muscle vs Fat
This BMI calculator may show "overweight" for muscular athletes. Use our body fat calculator instead.
Age Not Considered
This BMI calculator uses same ranges for all adults. Elderly may need different standards.
Not for Athletes
This BMI calculator may be inaccurate for bodybuilders and athletes with high muscle mass.
Doesn't Show Fat Distribution
This BMI calculator can't tell where fat is stored. Belly fat is more dangerous than hip fat.
Frequently Asked Questions
Common questions about BMI and this BMI calculator
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