What Is Your Roof Pitch?

Calculate roof pitch, slope, rise, run, and angle with easy conversions between ratios, degrees, and percentages.

Roof Pitch Calculator – Homes Remodeler

Inputs

Enter any two dimensions — or a pitch — and the rest update live. No Save.

Units
Roof dimensions
ft
ft
ft
Leave blank to calculate from rise + run (Pythagoras).
Or enter pitch directly
:12
Changing a pitch field recalculates rise from the current run (or run from rise if run is empty).
Common pitches

Roof Pitch Planning Ideas

Find rise, run, rafter length, and pitch in degrees, percent, or x:12 before you build or reroof.

What you get

  • Rise, run, and rafter length
  • Pitch in degrees, %, and x:12
  • Category: flat, low, conventional, high
  • Roof pitch multiplier for area

Helpful extras

  • Feet, inches, meters, or centimeters
  • Common pitch presets (2:12–12:12)
  • Live triangle diagram
  • Walkability guidance by pitch

How we calculate

  • rafter² = rise² + run²
  • pitch% = rise ÷ run
  • angle = arctan(rise ÷ run)
  • x:12 = (rise ÷ run) × 12

A 4:12 pitch rises 4 inches for every 12 inches of run — about 18.4° or 33.3%. It’s a common conventional pitch for asphalt shingles in many U.S. homes.

About 6:12 (26.5°) or less is generally easier to walk. Steeper pitches need more caution or special equipment. Never take risks on a roof — falls can be fatal.