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Grade / Slope Converter

Percent, degrees, ratio, or rise/run, all at once.

Percent
5.00%
Degrees
2.86°
Ratio
1:20.0

Common reference grades

  • Wheelchair ramp: max 8.33% (1:12)
  • Highway max: 6%
  • Steepest interstate (I-70): 7%
  • Lombard Street: 27%
  • Steepest road in the world (Baldwin Street, NZ): 35%

Slope, grade, and angle all describe the same thing in different units. Percent grade is rise/run × 100. Degrees use the arctangent. The 1:X ratio is the run for one unit of rise (the steeper the slope, the smaller X).

About

Enter slope in any of four forms (rise/run, percent, degrees, or 1:X ratio) and the others are computed. Includes a reference list of real-world grades so you know whether 8% is steep or normal.

How to use

  1. Pick an input mode.
  2. Enter the value.
  3. Read all four representations.

FAQ

How steep is a wheelchair ramp?+

ADA caps at 1:12, which is 8.33% or 4.76°. Most ramps you've used are at or below that.