Gutter Slope Calculator
Estimate total gutter drop, slope percentage, hanger quantity and installed-length cost from run length and a chosen slope rate.
Default project preview
2 in
Number of runs
2
Total gutter length
80 ft
Slope percentage
0.417%
Hangers per run
21
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Imperial drop = run length ÷ 10 × inches per 10 feet. Metric drop = run length × millimetres per metre. Hangers = round up (run length ÷ spacing) + 1.
FAQ
Gutter Slope Calculator questions
Should a long gutter slope toward one or two outlets?+
That depends on roof runoff, outlet locations and system layout. Long runs are often divided around a high point.
Why calculate slope percentage?+
It provides a unit-independent way to compare the selected vertical drop with the horizontal run.
Does the calculator size the downspout?+
No. Use the downspout and roof-drainage calculators for preliminary runoff capacity.