BMI Calculator (Body Mass Index)
Calculate BMI and BMI Prime with WHO classification categories, plus a clear explanation of why BMI alone is not enough for athletes.
Results
- Body mass index
- 24.5
- Weight (kg) / height (m)2
- BMI Prime
- 0.98
- BMI / 25 - below 1.0 is inside the healthy range
- WHO category
- Healthy range (18.5-24.9)
- Healthy weight range for your height
- 56.7 kg - 76.3 kg
- BMI 18.5-24.9 converted to bodyweight
WHO BMI classification
| BMI | Category |
|---|---|
| < 18.5 | Underweight |
| 18.5 - 24.9 | Healthy range |
| 25 - 29.9 | Overweight |
| 30+ | Obesity |
How it works & limitations
What BMI can and cannot tell you
BMI is a quick screening index of weight relative to height. It does not measure body fat, so muscular athletes are often misclassified as overweight. For jumpers, pair BMI with body-fat or waist-to-height measurements before drawing conclusions.
BMI Prime
BMI Prime = BMI / 25. Values below 1.0 are inside the healthy range; 1.2 means 20% above the boundary. It makes BMI easier to reason about across different people.
The athlete check
If you add body fat, the calculator compares BMI with body-fat-based categories. A high BMI with low body fat is usually muscle, not excess fat - a common pattern in jump athletes that BMI alone gets wrong.
Sources
Last updated 2026-08-13
- World Health Organization. (2000). Obesity: preventing and managing the global epidemic. WHO Technical Report Series 894.
Screening only. BMI does not diagnose health or body composition - especially for athletes - and should not be used alone for training or medical decisions.
Frequently asked questions
Is BMI accurate for athletes?
BMI only uses height and weight, so it cannot distinguish muscle from fat. A muscular jumper can be classified as overweight despite being lean. Use it as a screening tool, and check body-fat or waist-to-height measurements for a truer picture.
What is BMI Prime?
BMI Prime is BMI divided by 25, the upper limit of the healthy range. A value of 1.0 means you are exactly at that boundary, 1.2 means 20% above it. It makes BMI easier to compare across people.