Roof Pitch Gauge +
Slope that locks itself, x/12
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Lay the phone on the roof and the pitch locks by itself. Calibrate for your case, then check rafter factors and IRC minimum slopes for every face of the job.
Roof Pitch Gauge reads the slope of a roof from your phone's motion sensor. Lay the phone on the roof deck or a rafter, hold still, and the reading locks by itself — lift the phone and the number stays on screen.
▶ OPEN AND READ
The gauge is the first screen: one big number in the notation used where you work, with the other three underneath.
• x/12 rise over run, shown to the nearest ½ (≈ marks a rounded value)
• degrees
• percent grade
• rise per 10 (寸 / 치)
Tap the number to switch. A stability ring fills while the phone is still and turns green when the reading locks. It only shows that the phone has stopped moving; it does not rate the reading.
▶ CALIBRATE FOR YOUR PHONE AND CASE
A case or camera bump tilts the phone a little. Calibrate once:
• Turn-around: read a spot, turn the phone end-for-end, read it again. Works on the roof itself.
• Level surface: one reading on a surface you know is level.
The app refuses a calibration that does not add up (a surface that is not level, or a phone that was not turned) and tells you when the case tilt is larger than usual. The calibration date is shown on the gauge.
▶ JOB READINGS
Tap Add to job for each face — front, back, porch, garage. For the reading you pick, the Job page shows:
• the common rafter / area factor and the hip / valley factor
• minimum slopes by roof covering from the 2021 International Residential Code, section R905: asphalt shingles, clay and concrete tile, metal roof shingles, mineral-surfaced roll roofing, slate, wood shingles and wood shakes, each marked Below minimum, Allowed with double underlayment or Meets minimum, with the section number
Checks use the unrounded value, so 1.9/12 is not passed as 2/12. The IRC is a US model code; local codes and the product's instructions can require more.
▶ SIGHT FROM THE GROUND
Hold the phone up, camera on the roof, and turn it until the yellow line lies on the roof edge. The result is the apparent slope in the image and is labelled rough: it matches the real pitch only when you face the gable end square-on at about its height. No photo is taken or stored.
▶ ESTIMATE
Send a reading to the estimator: rafter length, roof area, roofing squares and shingle bundles for a simple gable roof, hip / valley rafter length, waste and an optional material cost. Estimates saved in the earlier version stay in the list.
▶ PITCH TABLE AND GUIDE
Common pitches from 1/12 to 18/12 with degrees, percent, rise per 10, rafter factor and the IRC minimum that starts at each one, plus a short guide to measuring safely.
Readings come from the phone's sensor and depend on how flat the phone sits. Use them for planning, and check critical measurements with a level.
Works offline, no account. Supported by ads: an ad may appear when you open the app, a banner is shown at the bottom, and a full-screen ad may follow a saved estimate. Sharing job readings or an estimate as text can be unlocked for 24 hours by watching an ad.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Version 2.0 is rebuilt from the ground up. The gauge is now the first screen and locks the reading on its own once the phone is still. Calibrate for your case with a turn-around reading, add each roof face to the job for rafter factors and IRC R905 minimum slopes, take a rough camera sight from the ground, and use the app in 30 languages. Your saved estimates are kept.
The developer, heekyung moon, 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 Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
- Identifiers
- Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Identifiers
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- heekyung moon
- Size
- 55.5 MB
- Category
- Utilities
- Compatibility
Requires iOS 16.4 or later.
- iPhone
Requires iOS 16.4 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
- Age Rating
18+
- 18+
- Contains
Advertising
- Copyright
- © 2026 Moon