Gutter Calculator
Calculate gutters, downspouts, hangers, and corners for your home
Fast estimate from roof perimeter
Quick presets
ft
Gutter Length
0 ft
0 downspouts needed
PRO
Professional Calculator
Full gutter system design with sizing, downspouts, and accessories
sq ft
ft
Estimated Materials
60 bundles
Roof Area
1,792 sq ft
Squares
17.9
Detailed Breakdown
Roof Area1,792 sq ft
With Waste1,971 sq ft
Roofing Squares17.9
Bundles60
How to Use This Calculator
On the Quick Estimate tab, enter the total linear feet of gutter you need (measure all eave edges) and select your gutter size. Choose the number of stories so the calculator can size your downspouts. You will instantly see gutter length, downspout count, and hanger quantity.
The Complete System tab lets you fine-tune with inside corners, outside corners, end caps, and optional gutter guards. This gives you a full parts list you can take to a supplier or use to compare contractor quotes.
Finally, the Cost Estimate tab prices out your system by material — vinyl, aluminum, steel, or copper. Choose seamless (professional) or sectional (DIY) to see how installation method affects cost. The calculator includes all components: gutters, downspouts, hangers, elbows, connectors, and splash blocks.
The Formula
Gutter Length = Sum of all eave measurements (linear feet)
Downspout Count = Gutter Length / 30 (round up, minimum 1 per section)
Downspout Length (each) = Wall Height + 4 ft (ground extension)
Hangers = Gutter Length / 2 (one every 24 inches)
Elbows = Downspout Count x 3 (2 at gutter + 1 at ground)
Material Cost = Gutter Length x $/ft + Downspout Count x Downspout Length x $/ft
Total Installed = Material Cost + Labor ($3-8/ft depending on material and stories)
Example Calculation
For an average home with 160 ft of 5-inch aluminum gutters, 1.5 stories:
• Gutter: 160 linear feet of 5" K-style
• Downspouts: 160 / 30 = 6 downspouts (2x3 aluminum)
• Downspout length each: 15 ft + 4 ft = 19 ft (114 ft total)
• Hangers: 160 / 2 = 80 hidden hangers
• Elbows: 6 x 3 = 18 elbows
• End caps: 4 end caps
• Inside corners: 2, Outside corners: 2
• Material: 160 x $4 + 114 x $2 + accessories = $910
• Labor: 160 x $5 = $800
• Total installed: $1,710
• Gutter: 160 linear feet of 5" K-style
• Downspouts: 160 / 30 = 6 downspouts (2x3 aluminum)
• Downspout length each: 15 ft + 4 ft = 19 ft (114 ft total)
• Hangers: 160 / 2 = 80 hidden hangers
• Elbows: 6 x 3 = 18 elbows
• End caps: 4 end caps
• Inside corners: 2, Outside corners: 2
• Material: 160 x $4 + 114 x $2 + accessories = $910
• Labor: 160 x $5 = $800
• Total installed: $1,710
Frequently Asked Questions
How many feet of gutter do I need?
Measure every eave (horizontal roof edge) where you want gutters. For most homes, this is the full perimeter minus the gable (triangular) ends. A typical single-story ranch with a 1,500 sq ft footprint needs about 130-170 linear feet of gutter. Multi-story homes may need gutters at each roof level.
How many downspouts do I need?
The general rule is one downspout for every 20-30 feet of gutter run, and at least one per gutter section. For 5-inch K-style gutters, one 2x3 downspout handles about 600 sq ft of roof area in moderate rainfall. In high-rainfall zones (Southeast US, Pacific Northwest), increase to one downspout per 20 feet.
What size gutters do I need?
5-inch K-style gutters are standard for most homes and handle roofs up to about 5,500 sq ft. Upgrade to 6-inch if your roof is larger than 5,500 sq ft, if you live in a high-rainfall area (over 4 inches/hour), or if you have steep pitches that accelerate water flow. Half-round gutters hold about 30% less water than K-style of the same size.
How much do gutters cost in 2026?
Installed gutter prices in 2026: vinyl $3-5/ft, seamless aluminum $6-12/ft, galvanized steel $8-14/ft, and copper $25-45/ft. For a typical 160-ft aluminum gutter system with downspouts, expect to pay $1,200-2,000 total. Add $1-10 per foot for gutter guards. Professional installation for a standard home takes 4-6 hours.
Should I get seamless or sectional gutters?
Seamless gutters are better in almost every way — no joints to leak, cleaner appearance, and custom-fit to your home. They cost only 10-20% more than sectional and last 20-30 years. Sectional (10-ft sections joined by connectors) are the only option for DIY since seamless requires a portable forming machine. If you are hiring a pro, always choose seamless.