BMI Calculator
Calculate your Body Mass Index (BMI) and body fat percentage. Get insights into your health and fitness levels with detailed analysis and recommendations.
BMI Calculator
BMI Categories
BMI Calculator Features
BMI Calculation
Accurate BMI calculation with health categories
Body Fat Analysis
Estimate body fat percentage using BMI
Ideal Weight Range
Get your healthy weight target range
Multiple Units
Support for metric and imperial units
Health Insights
Detailed health recommendations
Health Categories
Clear BMI and body fat categories
How to Use Our BMI Calculator
Step-by-Step Guide
- 1Enter your height in the height field
- 2Enter your weight in the weight field
- 3Select your preferred unit system (metric or imperial)
- 4Get your BMI result and health category instantly
BMI Categories
- Underweight: BMI less than 18.5
- Normal Weight: BMI 18.5-24.9
- Overweight: BMI 25-29.9
- Obese: BMI 30 or higher
When to Use Our BMI Calculator
Health Monitoring
Track your BMI over time to monitor health changes and maintain a healthy weight range.
Fitness Goals
Set and track fitness goals, monitor progress, and adjust workout and nutrition plans.
Medical Consultations
Prepare BMI information for doctor visits and health assessments.
Insurance & Health Forms
Calculate BMI for insurance applications, health screenings, and medical forms.
Nutrition Planning
Use BMI as a starting point for nutrition planning and dietary adjustments.
Research & Studies
Calculate BMI for research purposes, health studies, and statistical analysis.
Frequently Asked Questions
What is BMI and how is it calculated?
BMI (Body Mass Index) is a measure of body fat based on height and weight. It's calculated by dividing weight in kilograms by height in meters squared (kg/m²). For example, if you weigh 70kg and are 1.75m tall, your BMI is 70 ÷ (1.75 × 1.75) = 22.9. It provides a general indication of whether a person is underweight, normal weight, overweight, or obese.
What is a healthy BMI range?
A healthy BMI typically falls between 18.5 and 24.9 for adults. BMI below 18.5 is considered underweight, 25-29.9 is overweight, and 30 or above is considered obese. Class I obesity is 30-34.9, Class II is 35-39.9, and Class III (severe) obesity is 40 or above. These ranges are based on research linking BMI to health risks.
Is BMI accurate for everyone?
BMI is a useful screening tool but has limitations. It may not be accurate for athletes with high muscle mass, bodybuilders, older adults with reduced muscle mass, pregnant women, or people with different body compositions. Muscle weighs more than fat, so muscular individuals may have high BMI despite being healthy. It's best used as a general health indicator alongside other factors like waist circumference and body fat percentage.
Is the BMI calculator free to use?
Yes! Our BMI calculator is completely free to use with no registration required. You can calculate your BMI and get health insights without any restrictions, hidden fees, or premium features. Use it as many times as you need to track your health journey.
What information do I need to calculate BMI?
You only need your height and weight to calculate BMI. Our calculator supports both metric (kg, cm) and imperial (lbs, ft/in) units. Simply enter your measurements and get instant BMI results with health category classification and personalized recommendations based on your results.
Does the tool store my personal information?
No, your personal information is never stored or transmitted to our servers. All calculations happen locally in your browser using JavaScript, ensuring complete privacy and security of your health data. Your height, weight, and BMI results never leave your device.
What do the different BMI categories mean?
Underweight (BMI < 18.5): May indicate malnutrition or health issues. Normal weight (18.5-24.9): Associated with lowest health risks. Overweight (25-29.9): Increased risk of health problems. Obese (≥30): Significantly elevated risk of diabetes, heart disease, and other conditions. These are general guidelines and individual health varies.
How often should I check my BMI?
For weight management, checking BMI monthly is sufficient to track progress. More frequent checks may show normal fluctuations due to water retention or recent meals. Focus on long-term trends rather than daily changes. Combine BMI tracking with other health metrics for a complete picture.
Can children use this BMI calculator?
This calculator is designed for adults aged 18 and over. Children and teenagers require special BMI-for-age percentile charts as their body composition changes during growth. Pediatric BMI takes into account age and sex, using different calculation methods. Consult a pediatrician for children's BMI assessments.
What should I do if my BMI is outside the healthy range?
If your BMI is outside 18.5-24.9, consult a healthcare provider for personalized advice. They can assess your overall health, body composition, and recommend appropriate diet and exercise plans. Remember that BMI is just one health indicator - factors like diet quality, physical activity, and genetics also matter significantly.
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