BAI was designed to estimate fat percentage directly. Later studies found it is not consistently better than BMI, so treat it as one estimate among several.
How to use the Body Adiposity Index Calculator
- Hip circumference
- Height
Results update as you type, and every field accepts the units shown in its menu.
How it works
Divide hip circumference in centimetres by height in metres raised to 1.5, then subtract 18.
Inputs explained
| Field | What to enter |
|---|---|
| Hip circumference | Units: cm, m, mm, in, ft |
| Height | Units: cm, m, mm, in, ft |
Example values
How the main result changes when Hip circumference changes and everything else stays at the example values above:
| Hip circumference (cm) | Body adiposity index (% body fat) |
|---|---|
| 50 | 3.6 |
| 75 | 14.4 |
| 100 | 25.2 |
| 125 | 36 |
| 150 | 46.8 |
| 200 | 68.4 |
Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.
Formula
BAI = hip (cm) ÷ height (m)^1.5 − 18Worked example
Inputs — Hip circumference: 100 cm; Height: 175 cm.
Results — Body adiposity index = 25.2 % body fat.
Frequently asked questions
Do I need my weight?
No, only hips and height.
Is BAI accurate?
It can over- or under-estimate fat in some groups; compare with other methods.
What formula does the Body Adiposity Index Calculator use?
BAI = hip (cm) ÷ height (m)^1.5 − 18.