Gutter Length Calculator
Feet of gutter and downspouts needed for a roof.
Enter your values
ⓘ Live results
Results
- Gutter needed
- 150 ft
- Downspouts needed
- 5
- End caps needed
- 4
- 10-ft gutter sections
- 15
Quick answer
Gutter length equals your roof's eave perimeter; downspouts are typically one per 30-40 feet of gutter run.
downspouts = ceil(gutter length / 35)
How to use the Gutter Length Calculator
- 1Measure the total length of eaves where gutters will be installed.
- 2Use a downspout every 30-40 feet of gutter run for good drainage.
- 3Buy gutter in standard 10-ft sections plus corner and end cap pieces as needed.
Worked example
Using the values the calculator loads with:
Inputs
- Roofline eave length (total)150 ft
- Downspout spacing35 ft
Results
- Gutter needed150 ft
- Downspouts needed5
- End caps needed4
- 10-ft gutter sections15
Frequently asked questions
How many downspouts does a typical house need?
Most homes need one downspout per 30-40 feet of gutter, so a typical house has 4-6 downspouts total.
What size gutters should I use?
5-inch K-style gutters are standard for most homes; larger roofs or heavy rainfall areas may need 6-inch gutters.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.