If you’re building or renovating a roof, knowing your roof pitch is essential. Use our free Roof Pitch Calculator to quickly determine the slope of your roof in percentage, degrees, and as a rise-over-run ratio. Just enter the rise and run, and get instant results — no math required.

How to Use the Roof Pitch Calculator

1. Enter the Rise — Measure the vertical distance from the top of the wall to the peak of the roof.
2. Enter the Run — Measure the horizontal distance from the edge of the roof inward to where the rise was measured.
3. Click “Calculate Roof Pitch” — Your results will appear instantly, including:
   • Slope percentage
   • Roof pitch (rise:run)
   • Roof angle in degrees
   • Rafter length
   • Roof type based on slope steepness

This tool works for homeowners, contractors, DIY builders, or anyone needing fast, accurate roof pitch information.

Why Roof Pitch Matters

Your roof pitch determines:

• The style and look of your roof
• The materials you should use (steeper roofs shed water better)
• Building code compliance
• Accurate material estimates

Whether you’re installing shingles, metal panels, or checking drainage, knowing your roof pitch is critical to avoid mistakes.

Roof Pitch Formula

For reference, here’s the basic formula used in our calculator:

Pitch (Ratio) = Rise ÷ Run
Pitch (%) = (Rise ÷ Run) × 100
Angle (Degrees) = arctangent (Rise ÷ Run)
Rafter Length = √(Rise² + Run²)

Use the calculator to find your exact roof specifications.

Ready to Calculate?

Scroll up and enter your measurements now to get your roof pitch instantly!