Convert rise and run into slope percent (grade). Ideal for ramps, roads, driveways and ADA checks.
| Input | Result |
|---|---|
| rise 1, run 20 | 5% (1:20 ramp) |
| rise 10, run 100 | 10% |
| rise 100, run 100 | 100% (45°) |
It is how much the ground rises for every 100 units of horizontal distance. A 5% slope rises 5 units per 100 units of run.
Angle = arctan(rise ÷ run). A 100% slope is arctan(1) = 45°; a 5% slope is about 2.86°.
Many accessibility standards (e.g. ADA in the US) cap ramps at 1:12, which is about 8.33%. Always check the rules that apply to your project.