Slope Calculator
Calculate slope as a percentage, ratio, or degrees.
How It Works
Slope % = Rise ÷ Run × 100. Ratio = Rise ÷ Run × 12 (in 12). Angle = atan(Rise ÷ Run).
Example
6 ft of rise over 100 ft of run: 6% slope, 0.7 in 12, 3.4°.
Frequently Asked Questions
What is the difference between % and degrees?
Percent is the vertical rise per horizontal run × 100; degrees is the actual angle from horizontal.
What is a good drainage slope?
Ground should slope away from foundations at about 5% (2.4°) — roughly 6 in over 10 ft.
What does "X in 12" mean?
The rise in inches per 12 inches (1 ft) of run — the same notation roofers use for pitch.