Enter the difference in elevation between edges (ft) and the lane width (ft) into the Cross Slope Calculator. The calculator will evaluate and display the Cross Slope. 

Cross Slope Formula

The following formula is used to calculate the Cross Slope. 

CS = E / W * 100
  • Where CS is the Cross Slope (%)
  • E is the difference in elevation between edges (ft) 
  • W is the lane width (ft) 

To calculate a cross slope, divide the elevation between edges by the lane width.

How to Calculate Cross Slope?

The following example problems outline how to calculate Cross Slope.

Example Problem #1:

  1. First, determine the difference in elevation between edges (ft).
    • The difference in elevation between edges (ft) is given as: 2.5.
  2. Next, determine the lane width (ft).
    • The lane width (ft) is provided as: 50.
  3. Finally, calculate the Cross Slope using the equation above: 

CS = E / W * 100

The values given above are inserted into the equation below and the solution is calculated:

CS = 2.5 / 50 * 100 = 5.00 (%)


Example Problem #2: 

For this problem, the variables needed are provided below:

difference in elevation between edges (ft) = 6.7

lane width (ft) = 198

This example problem is a test of your knowledge on the subject. Use the calculator above to check your answer. 

CS = E / W * 100 = ?