Pounds to BMI Calculator
Calculate Body Mass Index using weight in pounds
Enter Your Details
Enter weight between 50-500 pounds
Feet
Inches (0-11)
Your BMI Results
Your Body Mass Index
—
BMI Categories
Metric Equivalent
Weight
— kg
Height
— cm
Common BMI Examples
| Weight (lbs) | Height | BMI | Category |
|---|---|---|---|
| 120 | 5′ 4″ | 20.6 | Normal |
| 150 | 5′ 9″ | 22.2 | Normal |
| 180 | 5′ 6″ | 29.1 | Overweight |
| 200 | 5′ 10″ | 28.7 | Overweight |
| 220 | 5′ 8″ | 33.5 | Obesity |
| 250 | 6′ 0″ | 33.9 | Obesity |
These examples help verify our calculator matches standard BMI calculations
How the Pounds to BMI Calculator Works
This pounds to BMI calculator takes your weight in pounds and height in feet and inches to calculate your Body Mass Index instantly. BMI is a simple numerical measure that helps assess whether your weight is appropriate for your height.
BMI Formula: BMI = (Weight in pounds × 703) ÷ (Height in inches)²
First, we convert your height from feet and inches to total inches. Then we apply the formula above. The constant 703 converts from pounds and inches to the standard BMI metric.
Understanding Your BMI Result
Your BMI number falls into one of four main categories established by health organizations. These categories provide a general indication of whether your weight might be affecting your health.
It’s important to remember that BMI is a screening tool, not a diagnostic one. It doesn’t measure body fat directly, nor does it account for muscle mass, bone density, overall body composition, or racial and sex differences.
For athletes and very muscular individuals: BMI may classify you as overweight even when you have a healthy body fat percentage. Muscle weighs more than fat, so your BMI might be higher than expected.
BMI Categories Explained
Underweight (BMI below 18.5): This may indicate insufficient body weight for your height. Being underweight can be associated with health issues including nutritional deficiencies, osteoporosis, and decreased immune function.
Normal weight (BMI 18.5 to 24.9): This range is generally associated with the lowest risk of weight-related health problems for most people. Maintaining a weight in this range through balanced nutrition and regular physical activity is recommended.
Overweight (BMI 25 to 29.9): This indicates excess body weight for your height. Being overweight increases your risk for various health conditions including type 2 diabetes, high blood pressure, and heart disease.
Obesity (BMI 30 and above): This category indicates a high amount of excess body weight. Obesity is associated with significantly increased risk of serious health conditions and reduced life expectancy.
Important limitation: BMI doesn’t distinguish between muscle and fat. A muscular athlete and someone with high body fat could have the same BMI. Always consult a healthcare professional for a comprehensive health assessment.
How to Use This Calculator Effectively
For accurate results, measure your height without shoes and weigh yourself in lightweight clothing. It’s best to weigh yourself at the same time of day (morning is often most consistent) and under similar conditions each time.
If you’re tracking changes over time, calculate your BMI monthly rather than daily or weekly. Body weight naturally fluctuates due to water retention, food intake, and other factors.
Common Questions About BMI Calculation
Why does the calculator use 703 in the formula?
The number 703 converts the calculation from pounds and inches to the standard metric formula (kg/m²). The standard BMI formula is weight in kilograms divided by height in meters squared. Since we’re using pounds and inches, we need the conversion factor: 1 kg = 2.20462 pounds and 1 meter = 39.3701 inches.
Is BMI different for men and women?
The same BMI formula applies to both men and women. However, women typically have more body fat than men at the same BMI. The categories (underweight, normal, overweight, obese) are the same for both sexes.
Does BMI work for children and teenagers?
This calculator is designed for adults (20 years and older). For children and teens, BMI is calculated differently using percentiles that account for age and sex. Pediatricians use growth charts specifically designed for younger populations.
What if my BMI says I’m overweight but I look and feel healthy?
BMI is just one indicator of health. If you’re physically active, eat a balanced diet, have good blood pressure and cholesterol levels, and feel energetic, you might be healthier than your BMI suggests. Consider other measurements like waist circumference or body fat percentage for a more complete picture.
Beyond BMI: Other Health Indicators
While BMI is useful for population-level studies and quick assessments, consider these additional measurements for a more complete health picture:
Waist circumference: Measure around your natural waist (just above your hip bones). For most adults, a waist circumference over 35 inches for women or 40 inches for men increases health risks regardless of BMI.
Waist-to-hip ratio: Divide your waist measurement by your hip measurement. A ratio above 0.85 for women or 0.90 for men indicates increased health risk.
Body fat percentage: This directly measures fat mass versus lean mass. Healthy ranges are typically 20-30% for women and 10-20% for men, though these vary by age.
When to Consult a Healthcare Professional
If your BMI falls outside the normal range, or if you have concerns about your weight, consult with a doctor or registered dietitian. They can provide personalized advice based on your health history, lifestyle, and specific needs.
Remember that weight management is about overall health, not just a number on a scale or BMI calculator. Focus on sustainable habits like regular physical activity, balanced nutrition, adequate sleep, and stress management rather than quick fixes.
Final thought: Your BMI is a starting point for understanding your weight in relation to your height. Use it as one tool among many to assess your health, and always pair it with other indicators and professional medical advice.
Frequently Asked Questions
How accurate is this pounds to BMI calculator?
This calculator uses the standard BMI formula endorsed by the CDC and WHO. It’s mathematically accurate for converting pounds and inches to BMI. However, remember that BMI itself has limitations as a health indicator.
Why do I need to convert feet to inches in the calculation?
The BMI formula requires height in inches squared. Since people in the US typically measure height in feet and inches, our calculator automatically converts 5’9″ to 69 inches (5×12 + 9 = 69) before applying the formula.
Can I use this calculator if I know my weight in kilograms?
This calculator is specifically designed for pounds. If you know your weight in kilograms, multiply by 2.20462 to convert to pounds first, or use a metric BMI calculator that accepts kilograms and centimeters.
What’s considered a healthy BMI for adults?
For adults aged 20 and older, a BMI between 18.5 and 24.9 is generally considered healthy. However, individual factors like muscle mass, age, and ethnicity can affect what’s optimal for you personally.
How often should I check my BMI?
For most people, checking BMI once a month is sufficient. Daily or weekly measurements aren’t helpful because normal weight fluctuations can be misleading. Focus on long-term trends rather than day-to-day changes.