Your Fitness
Score
Get a single score out of 100 that combines your BMI, body fat, and calorie balance. See where you stand — and share it.
What Is the IndexBody Fitness Score?
The Fitness Score is a composite index out of 100 that combines four widely used health screening measurements — body mass index (BMI), estimated body fat percentage, waist-to-height ratio, and self-reported activity level — into a single number. It is designed to give you a quick, easy-to-share snapshot of where your current body composition and activity habits sit relative to general population health guidelines. It is not a diagnostic tool and does not measure cardiovascular fitness, strength, endurance, or any clinical biomarker directly.
How the Score Is Calculated
Each of the four components below is scored on a 0–100 scale using published reference ranges, then combined using a weighted average: body fat percentage (35%), BMI (25%), waist-to-height ratio (20%), and activity level (20%). Body fat carries the largest weight because it is a closer proxy for body composition than BMI alone, which cannot distinguish muscle mass from fat mass.
BMI (Body Mass Index)
BMI = weight (kg) ÷ height (m)². It estimates whether your weight is in a typical range for your height and is used here only as a population-level screening indicator, not a measure of body fat or overall fitness.
Body Fat % (U.S. Navy Method)
Estimated from neck, waist, and height using the U.S. Navy circumference formula. This is a practical estimate, not a substitute for a DEXA scan, hydrostatic weighing, or other clinical body-composition test.
Waist-to-Height Ratio
Waist circumference divided by height. Research has linked a ratio above roughly 0.5 to increased cardiometabolic risk, making this a useful proxy for abdominal fat distribution.
Activity Level
Derived from your selected activity multiplier and weekly exercise hours. It reflects how much movement you report, not measured cardiorespiratory fitness (e.g. VO2 max).
What Your Result Means
A higher score generally reflects a body composition and activity pattern that aligns more closely with population health guidelines from sources such as the WHO and CDC. A lower score is not a judgment of your worth or a prediction about your health outcomes — it simply flags areas (weight, body composition, waist proportion, or activity) where small, sustainable changes tend to have the most impact. Formulas like BMI and the Navy body-fat method are population estimates and are known to be less accurate for athletes, older adults, pregnant people, and some ethnic groups, so treat your score as a general indicator rather than an exact measurement.
Using This Score to Guide Next Steps
The score breakdown highlights which of the four factors is holding your overall number down. If your Body Comp or Weight Score is lower than the others, our body fat calculator and calorie calculator can help you set a realistic, gradual target. If your Activity score is low, aim to gradually build toward the commonly cited guideline of 150+ minutes of moderate activity per week. Sustainable progress is typically measured in weeks and months, not days, and results vary from person to person based on genetics, medical history, and consistency.
Limitations
- This score is an educational estimate, not a medical or diagnostic assessment.
- It does not account for muscle mass, bone density, medical conditions, medications, or pregnancy.
- The underlying formulas (BMI, Navy body fat, waist-to-height ratio) are population averages and may be less accurate for individuals outside typical ranges.
- No calculator can guarantee a specific health outcome; individual results depend on many factors outside this tool's scope.
This tool is for general informational and educational purposes only and does not constitute medical advice. See our full medical disclaimer · Privacy · Terms and methodology for details on the formulas used.