Enter the length of the gutter (ft) into the Gutter Slope Calculator. The calculator will evaluate and display the Gutter Slope. 

Gutter Slope Formula

The following formula is used to calculate the Gutter Slope. 

GS = .5 * L / 10 

  • Where GS is the Gutter Slope (inches of height needed)
  • L is the length of the gutter (ft) 

It’s recommended that for every 10 ft of length of gutter, there should be 1/2″ of drop.

How to Calculate Gutter Slope?

The following example problems outline how to calculate Gutter Slope.

Example Problem #1:

  1. First, determine the length of the gutter (ft). 
    • The length of the gutter (ft) is given as: 50.
  2. Finally, calculate the Gutter Slope using the equation above: 

GS = .5 * L / 10 

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

GS = .5 * 50 / 10  = 2.5 (inches of height/drop needed)


Example Problem #2: 

For this problem, the variables needed are provided below:

length of the gutter (ft) = 80

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

GS = .5 * L / 10  = ?