Slope Percentage Calculator

This calculator finds the slope percentage and angle in degrees and radians, given the rise and run of an incline.

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Created by: Jainisha Pansuriya

How to Calculate Slope Percentage

Formula used:

Slope (%) = (Rise ÷ Run) × 100

Angle (°) = tan-1 (Rise ÷ Run)

Radians = Degrees × (π ÷ 180)

Example 1:

Find the slope percentage and angle for:

  • Rise = 3.2 m
  • Run = 5.7 m

Apply the values in the formula:

= (3.2 ÷ 5.7) × 100

= 0.5614 × 100

= 56.14%

Angle = tan-1 (0.5614) = 29.31° or 0.51156 rad

Example 2:

  • Rise = 8 ft
  • Run = 25 ft

= (8 ÷ 25) × 100

= 0.32 × 100

= 32%

Angle = tan-1 (0.32) = 17.745° or 0.3097 rad

Quick Conversion Table

Slope (%)Angle (°)Angle (rad)
5%2.86°0.0499
10%5.71°0.0997
15%8.53°0.1489
20%11.31°0.1974
25%14.04°0.2450
30%16.70°0.2915
35%19.29°0.3367
40%21.80°0.3805
45%24.23°0.4229
50%26.57°0.4636
60%30.96°0.5404
70%34.99°0.6107
80%38.66°0.6747
90%41.99°0.7330
100%45.00°0.7854