02 / HOME & DIY
Roof pitch calculator.
Convert rise and run into pitch, angle and slope.
Preparing your workspace…
Questions & answers
What does a 6:12 roof pitch mean?
A 6:12 pitch rises 6 units for every 12 units of horizontal run. That is a 50% slope and approximately a 26.57° angle from horizontal. The ratio is the same in inches or centimetres.
Is run the full roof span or the sloped length?
Run is horizontal. For one slope of a symmetric gable roof, it is half the horizontal span between eaves. Entering the sloped length or the full span as the run gives the wrong pitch.
Can I use the result to cut rafters or order materials?
The result describes only the entered right triangle. It excludes overhangs, joints, cuts, roof openings and material waste. It does not determine structural capacity or a rafter-cutting plan.