Elevation Grade Calculator

How grade is calculated

Grade is the ratio of vertical rise to horizontal run, expressed as a percentage. A 10-foot rise over a 100-foot run is a 10 percent grade. The angle in degrees is the arctangent of that ratio.

Slope ratio expresses the same relationship as rise-to-run, such as 1:10 or 1:4. All three representations describe the same physical slope; the choice of format depends on the application.

Where grade calculations are used

Road engineers use grade to design safe driving gradients. Landscape architects use it to plan drainage and retaining walls. ADA accessibility standards specify maximum ramp grades. Construction crews use grade to set forms and verify that finished surfaces drain correctly.