Roof Pitch Calculator
Roof pitch, angle and rafter length from rise and run.
What it is
Roof Pitch Calculator turns a rise and a run into everything you need: the roof pitch as a standard X:12 ratio, the angle in degrees and the rafter length. It is a quick field tool for roofers, framers and DIY builders.
Screenshots
Features
Works in metres or feet. No internet, no account, no data collected.
Built for roofers, carpenters, framers and DIY builders sizing a roof, cutting rafters or checking a pitch on site. A fast, no-nonsense field tool.
- Pitch as a standard X:12 ratio
- Roof angle in degrees
- Rafter length (the sloped line from ridge to wall plate)
How it works
Pitch is the rise per 12 units of run. The angle is the arctangent of rise divided by run, and the rafter length is the hypotenuse of the rise and the run (the line from ridge to wall plate).
Honest limits
- Rafter length here is the sloped line from ridge to wall plate; add overhang and adjust for the ridge board when you cut.
Questions
How do I calculate roof pitch?
Divide the rise by the run and multiply by 12 to get the pitch as X:12. For example, a rise of 6 over a run of 12 is a 6:12 pitch.
What angle is a 6:12 roof pitch?
About 26.6 degrees: the angle is the arctangent of 6 divided by 12. Roof Pitch Calculator converts any rise and run to degrees.
How do I find rafter length?
Rafter length is the square root of rise squared plus run squared. The app calculates it in metres or feet.
Is Roof Pitch Calculator free?
Yes. It is free, needs no account and works offline.
Private and offline
Runs entirely on your phone and works offline. No account, no sign-up, and your data stays on your device. The app shows ads through Google AdMob; see the privacy policy. Privacy policy.
Free, with ads.
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