A gutter calculator helps you estimate the exact materials needed for a rain gutter installation — including linear feet of gutter, downspouts, corner pieces, end caps, and hangers. By entering your house dimensions and selecting which eaves get gutters, you get an accurate materials list with cost estimates to plan your project and avoid costly trips back to the supply store.
Gutter Materials Calculator
Gutters go on eave sides (where the roof slopes down), not gable/rake ends.
How to Use the Gutter Calculator
Installing or replacing gutters is essential for protecting your home's foundation, siding, and landscaping from water damage. Our free gutter calculator takes your house dimensions and turns them into a complete materials list — covering linear feet of gutter, downspouts, corner pieces, end caps, hangers, and cost estimates for both DIY and professional installation.
Step 1: Select Your House Shape
Start by choosing the shape that best matches your home. Rectangle is the most common — just two eave sides and two gable ends. L-Shape adds a wing extending from the main structure with additional corners and eave runs. U-Shape has two wings. Choose Custom if your home's layout is complex and you already know the total linear feet you need.
Step 2: Enter Your Dimensions
Measure the length and width of your house along the roofline from eave to eave. For L-shaped and U-shaped homes, enter the additional wing dimensions. These measurements determine the total linear feet of gutter needed. Measure from the outside edges of the fascia boards where the gutter will mount.
Step 3: Choose Eave Sides
Gutters are only installed on eave sides — the sides where the roof slopes down and water runs off. Gable ends (the triangular wall sides) do not need gutters. Check or uncheck each side to match your actual gutter plan. Most rectangular homes gutter both long sides (the eaves), but some homeowners only gutter the sides that face walkways, driveways, or gardens.
Step 4: Select Style and Material
Choose your gutter style — K-style 5" is the most popular residential choice, handling moderate rainfall well. K-style 6" handles heavier water flow for larger roofs. Half-round 5" gutters suit historic or European-style homes. Then pick your material: aluminum is the most common and affordable, vinyl is cheapest, steel is strongest, and copper is the premium long-lasting option.
Step 5: Review Your Results
The calculator displays total linear feet of gutter, number of downspouts (one per 30-40 feet of run), inside and outside corner pieces, end caps for each gutter run terminus, and hangers spaced every 3 feet. The cost estimate shows both material-only and professional installation price ranges based on your selected material. Use this list when getting contractor quotes or ordering supplies for a DIY installation.
FAQ
Is this gutter calculator free to use?
Yes, this gutter calculator is completely free with no limits or signup required. All calculations run in your browser, so your home measurements and cost data are never sent to a server or stored remotely.
Is my data private and safe?
Absolutely. Everything runs locally in your browser. Your house dimensions, material choices, and pricing data never leave your device. There are no cookies tracking your project data and no account required.
How many downspouts do I need?
The general rule is one downspout for every 30 to 40 linear feet of gutter. For areas with heavy rainfall, use the shorter 30-foot interval. This calculator uses 35 feet as the default spacing, which works well for most climates and roof sizes.
What is the difference between K-style and half-round gutters?
K-style gutters have a flat bottom and decorative front that resembles crown molding — they hold more water and are the most common residential style. Half-round gutters are semicircular and are often used on historic or European-style homes. Both come in 5-inch and 6-inch widths.
How far apart should gutter hangers be?
Gutter hangers or brackets should be spaced every 3 feet for most climates. In areas with heavy snow or ice, spacing them every 2 feet provides extra support. This calculator uses the standard 3-foot spacing to estimate the number of hangers you need.
Which gutter material is best for my home?
Aluminum is the most popular choice — lightweight, rust-resistant, and affordable at $3-5 per foot. Vinyl is the cheapest ($1-3/ft) but less durable in extreme temperatures. Steel ($4-8/ft) is very strong but can rust. Copper ($15-25/ft) is premium, develops a patina, and lasts 50+ years.
Do I need gutters on every side of my house?
Gutters are only needed on eave sides — the sides where the roof slopes down and water runs off. Gable ends (the triangular wall sides) and rake edges do not need gutters because water does not flow off those sides. Select which sides get gutters in the calculator for an accurate estimate.
How much does professional gutter installation cost?
Professional gutter installation typically costs $5 to $15 per linear foot, depending on material, gutter style, and local labor rates. This includes labor, hangers, and basic downspouts. Seamless aluminum gutters usually fall in the $6-$12 per foot range installed.