Calculate slope from two points or rise and run. Get slope m, percentage grade and angle in degrees, free and instant.
| Input | Result |
|---|---|
| (0,0) to (4,2) | m 0.5 · 50% · 26.57° |
| rise 1, run 20 | m 0.05 · 5% · 2.86° |
| (1,2) to (1,5) | undefined slope (vertical line) |
Subtract the y-coordinates to get rise and the x-coordinates to get run, then divide rise by run. For (0,0) and (4,2), m = (2−0) ÷ (4−0) = 0.5.
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°.
If rise is non-zero, the line is vertical and its slope is undefined. If rise and run are both zero, the two points coincide and no unique slope can be determined.
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.