FitCiYour details
Estimated body fat: –% · –
US Navy method; ±3–4 points of error. Measure at the same time and place and watch the trend.
How it is calculated
The US Navy method (Hodgdon-Beckett, 1984) estimates body fat from height, neck and waist (plus hip for women) with a log formula. Its average error against DEXA is ±3–4 points, more consistent than calipers or smart scales because it is less sensitive to hydration. Categories follow the ACE table: men 6–13% athlete, 14–17% fitness, 18–24% average; women 14–20% athlete, 21–24% fitness, 25–31% average.
A series of measurements matters, not one reading. Waist circumference alone is a strong health marker; FitCi charts your measurements.
Chart your measurements in FitCi
Waist, hip and arm measurements plus progress photos in one place; see the change weekly.