Slope Percentage Calculator
Use this calculator for grade of a slope: rise over run, times 100. A 3 unit rise across a 4 unit run is a 75% slope. A 1 in 20 grade is 5%.
How this is calculated
Divide rise by run, then multiply by 100. Use the same length unit for both measurements.
(rise / run) × 100
- 3 / 4 × 100 = 75%.
- 1 / 20 × 100 = 5%.
- Run cannot be zero, because that would be a vertical line.
A 100% slope is a 45-degree line: rise equals run. Slope percent is not an angle in degrees.
Not the same as
Slope percent is a ratio of lengths, not a part of a test score.
- X is what percent of Y? The arithmetic is the same ratio. This page keeps rise and run labels for grade and ramp questions. Open what-percent
Related tools
Slope questions
75%.
5%. Rise 1, run 20.
No. 100% means rise equals run, a 45-degree slope. A vertical line has run 0 and is undefined here.
Enter rise 1 and run 8, which is 12.5%. Convert other fractions first if needed.
No. It only reports rise over run as a percent.