BMI Calculator
Calculate your Body Mass Index and learn what it means for your health and fitness goals.
Calculate Your BMI
Enter your height and weight to calculate your Body Mass Index. BMI is a screening tool that provides a general indication of whether your weight falls in a healthy range.
Understanding Your BMI
| BMI Range | Category | What It Means |
|---|---|---|
| Below 18.5 | Underweight | May benefit from strength training and nutrition guidance to build lean mass |
| 18.5 - 24.9 | Normal | Healthy range — maintain with regular exercise and balanced nutrition |
| 25.0 - 29.9 | Overweight | May benefit from combined training and nutrition program for fat loss |
| 30.0+ | Obese | Professional guidance recommended — safe, progressive training program |
Note: BMI is a screening tool, not a diagnostic measure. It does not account for muscle mass, bone density, age, or sex. Consult a healthcare professional for a comprehensive health assessment.
BMI FAQ
What is BMI and how is it calculated?
Body Mass Index (BMI) is a simple calculation using height and weight to estimate body fat. The formula is weight (kg) divided by height (m) squared. For imperial units, it's weight (lbs) / height (inches)² × 703. While BMI is a useful screening tool, it doesn't directly measure body fat or account for muscle mass, age, sex, or ethnicity.
Is BMI an accurate measure of health?
BMI is a useful starting point but has limitations. It doesn't distinguish between muscle and fat — so a muscular athlete may have a "high" BMI despite being very fit. According to NASM-certified trainer Trevor Cassidy, BMI should be used alongside other metrics like body fat percentage, waist circumference, and functional fitness assessments for a more complete picture.
What BMI is considered healthy?
A BMI between 18.5 and 24.9 is generally considered a healthy range. Below 18.5 is underweight, 25-29.9 is overweight, and 30+ is classified as obese. However, these ranges are general guidelines — individual health depends on many factors beyond BMI alone.
How can a personal trainer help me reach a healthy BMI?
A personal trainer like Trevor Cassidy creates customized programs that address your specific situation. This includes progressive resistance training to build lean muscle (which improves body composition), cardiovascular programming, nutrition guidance, and ongoing accountability. Most clients see measurable improvements in body composition within 8-12 weeks of consistent training.
Want to Improve Your Body Composition?
BMI is just the start. Book a free consultation with Trevor Cassidy for a comprehensive fitness assessment and customized training plan.