Percent Grade to Degrees Calculator

Slope Percentage:
Input the percent of rise over run on a grade to convert to degrees of an angle.

How do you convert percent grade to degrees?

To convert, use this percent to degrees formula:
Degrees = Tan-1 (Grade Percent/100)


Example: With a slope percentage of 50%, degrees would be:

Degrees = Tan-1(.50)

Calculated out this gives an angle of 26.57 degrees.


Sometimes, grade is referred to as pitch, angle, rise, incline, or slope. Many different professions use slope or grade in describing an angle. For example, in construction, you may refer to the grade of a driveway, or the pitch of a roof on a building. Both are referring to types of angles. It can be tricky when some try to think of degrees and percentage of slope. For example, as you go from 0 degrees closer to a 90 degree angle, the percentage of slope increases to infinity. If you try different inputs on the calculator, you'll see as you increase the percent to higher numbers, the answer, in degrees, doesn't not increase at the same rate. There is a nice illustration on Wikipedia that helps illustrate this point.


This percent to degrees conversion is also useful when graphing statistics. By converting percentages to degrees, you can illustrate data on a pie chart. There are may different variations of pie charts, but, at their core, they all serve the purpose of easily determining different percentages.


As you might guess, the ability to convert percentages to degrees of an angle is very important in many aspects of engineering. This article from Greenbelt Consulting may shed some light on the relations of degrees, percent of slope, and gradient in engineering.