Frequently Asked Questions.
Why are slope measurements reported in degrees, and how do I convert them to other formats?
Slope can be measured and reported in several formats. For this website, slopes are reported in degrees because: clinometers (a tool for measuring slope angle degrees) are readily available and inexpensive to purchase or construct; clinometers are small and portable, the MonTECH staff collecting accessibility data in the field were most familiar with collecting slope measurements as degrees, and slope measurements collected in degrees are easily converted to other formats.
Rise over run equals the tangent of the angle in degrees. Percent slope equals the rise divided by the run multiplied by 100. For your convenience, the following table shows slope measurements equivalents for degrees, rise over run, and percent slope. For example, a 2.9 degree slope equals a slope that rises 1 unit in a run of 20 units (a 1 over 20 rise over run), equals a 5 percent slope.
| Degrees | Rise Over Run | Percent Slope |
|---|---|---|
| 1 | 1/57.3 | 1.7 |
| 1.5 | 1/38.2 | 2.6 |
| 2 | 1/28.6 | 3.5 |
| 2.5 | 1/22.9 | 4.4 |
| 3 | 1/19.1 | 5.2 |
| 3.5 | 1/16.3 | 6.1 |
| 4 | 1/14.3 | 7 |
| 4.5 | 1/12.7 | 7.9 |
| 5 | 1/11.4 | 8.7 |
| 5.5 | 1/10.4 | 9.6 |
| 6 | 1/9.5 | 10.5 |
| 6.5 | 1/8.8 | 11.4 |
| 7 | 1/8.1 | 12.3 |
| 7.5 | 1/7.6 | 13.2 |
| 8 | 1/7.1 | 14.1 |
| 8.5 | 1/6.7 | 14.9 |
| 9 | 1/6.3 | 15.8 |
| 9.5 | 1/6 | 16.7 |
| 10 | 1/5.7 | 17.6 |