BMI Calculator – Free Body Mass Index & Body-Weight Index Tool
Calculate your BMI with metric or imperial units
Calculate your body weight index and discover your ideal weight range
Body Mass Index (BMI) is a screening tool that uses your height and weight to estimate if you're at a healthy weight. While useful for population studies and initial assessments, BMI is not a diagnostic tool and doesn't measure body fat directly. It's one of several factors healthcare providers consider when evaluating your overall health status.
Enter Your Details
Your Results
Healthy Weight Range
Maintaining a healthy weight reduces the risk of chronic diseases.
Advertisement
(AdSense will load here)
Calorie Goals
Recommended Macronutrients
Health Risk Assessment
Recommendations
- Maintain a balanced diet rich in fruits, vegetables, lean proteins, and whole grains.
- Aim for at least 150 minutes of moderate-intensity exercise per week.
- Stay hydrated by drinking plenty of water throughout the day.
- Get 7-9 hours of quality sleep each night for optimal health.
Ready to Calculate
Enter your details and click the calculate button to see your personalized health metrics.
BMI Calculator Health Benefits
Using our body mass index calculator helps you monitor your health. Maintaining a healthy BMI reduces risks of heart disease, diabetes, and other conditions.
Body Mass Index Formula
Our BMI index calculator uses the standard formula: BMI = weight (kg) / (height (m))². For imperial measurements: (weight (lb) / (height (in))²) × 703.
BMI Calculator Considerations
While our body weight index calculator is accurate, BMI doesn't account for muscle mass, bone density, or overall body composition. Use it as one of several health metrics.
Understanding Your Body Mass Index (BMI)
The Body Mass Index (BMI) is a numerical value derived from your weight and height. Our BMI calculator uses this formula to help you understand if your weight is appropriate for your height. The BMI index calculator categorizes your result into underweight, normal weight, overweight, or obese.
How to calculate BMI manually
Metric formula: BMI = weight (kg) / [height (m)]²
Imperial formula: BMI = [weight (lb) / height (in)²] × 703
Example: For a person weighing 70 kg and height 1.75 m
BMI = 70 / (1.75)² = 70 / 3.0625 = 22.9 kg/m²
Body Weight Index Categories Chart
Is BMI always accurate?
BMI is a useful screening tool, but it has limitations. According to the CDC, BMI may not be accurate for:
- Athletes and muscular individuals (muscle weighs more than fat)
- Older adults who have lost muscle mass
- Certain ethnic groups (e.g., Asian populations may have health risks at lower BMI thresholds)
- Pregnant or breastfeeding women
Healthcare providers often use additional assessments like waist circumference, body fat percentage, and family history to evaluate health risks.
Healthy weight tips
- Aim for a balanced diet rich in fruits, vegetables, whole grains, and lean proteins
- Get at least 150 minutes of moderate physical activity per week
- Stay hydrated by drinking plenty of water
- Get adequate sleep (7-9 hours for most adults)
- Manage stress through mindfulness, relaxation techniques, or physical activity
BMI Categories
- Underweight: BMI less than 18.5
- Normal weight: BMI between 18.5 and 24.9
- Overweight: BMI between 25 and 29.9
- Obesity: BMI of 30 or greater
How to Use This BMI Calculator
- Enter your age, gender, height, and weight
- Select your activity level
- Click "Calculate BMI & More" to see your results
- Review your BMI, ideal weight range, and health recommendations
- Use the tabs to explore calorie needs and health insights