Skinfold: Estimates & Trends
Track body fat with calipers
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
No account or internet connection required. Estimate body fat from three-site skinfold readings and review trends stored only on your device.
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.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Version 1.3 makes skinfold measurements more flexible and easier to review:
• Calculate with one valid reading per site, or add a second and third reading to compare consistency.
• Switch all measurement inputs and displays between millimeters and inches.
• Optionally add the final body fat percentage estimate to Apple Health. Skinfold requests write-only access and never reads HealthKit data.
• Updated measurement, privacy, and support guidance in Simplified Chinese, English, and Japanese.
The developer, WENTIAN ZHANG, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- WENTIAN ZHANG
- Size
- 50.9 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 2 more
- English, Japanese, Simplified Chinese
- Age Rating
9+
- 9+
- Contains
Health or Wellness Topics
- Copyright
- © 2026 WENTIAN ZHANG