Skinfold: Estimates & Trends

Estimate body fat percentage from three-site skinfold readings, review changes over time, and optionally add the final estimate to Apple Health. No account is required.

CLEAR GUIDANCE, MILLIMETERS OR INCHES
See the Jackson–Pollock three-site locations for the selected sex, together with practical measurement instructions. Switch all readings between millimeters and inches while Skinfold keeps the calculation in the same underlying units.

RESULTS, LOCAL TRENDS, AND APPLE HEALTH
Skinfold uses the Jackson–Pollock three-site body-density equations and the Siri equation for converting body density to body fat percentage. It also shows general reference ranges. Save a result when you choose, then review changes in local history. Separately, you can choose to add only the final body fat percentage estimate to Apple Health. Skinfold never reads HealthKit data or writes raw skinfold readings.

PRIVATE AND OFFLINE
No registration, ads, analytics, developer cloud sync, or tracking. Calculations and saved local history stay on your device and are not sent to the developer. Apple Health access is optional, user-initiated, and write-only. Core features, the Privacy Policy, and Support are available offline.

SCOPE AND IMPORTANT INFORMATION
The source equations cover men ages 18–61 and women ages 18–55; results for women over 40 should be interpreted with care. The app does not calculate an estimate when the sum of the three site averages exceeds 120 mm (4.724 in). Skinfold estimates can vary with site placement, technique, calipers, individual differences, and the limits of the equations. This app is for general fitness and personal tracking only. It is not a medical device and does not provide medical advice, diagnosis, or treatment.