Gutter size, quantity & cost calculators

Free, no-signup gutter calculators for homeowners, DIYers and small contractors — figure out how much guttering to buy, what size gutters a roof needs, how many downspouts, and what a job should cost. Every tool runs on the measurements you take and the prices you enter, and shows its formula, a worked example and a reference table.

Gutter Calculators

The deterministic anchor: a gutter linear-feet calculator (sum of the eave runs), a gutter SIZE calculator (5" vs 6", K-style vs half-round, by roof area, pitch and rainfall), a downspout count calculator, a sections / hangers / end caps / corners / elbows calculator, a gutter slope calculator, a roof-pitch drainage-area calculator, and a gutter capacity / flow reference.

Gutter linear-feet calculatorAdd up to six eave runs to get the total linear feet of gutter you need. Free, instant, with the formula, a worked example and the corners-and-waste rule.Gutter size calculator (5" vs 6")Do you need 5-inch or 6-inch gutters? Enter roof footprint, pitch and rainfall to get the smallest K-style or half-round size that drains it.Downspout count calculatorHow many downspouts do you need? Runs both methods — roof area per outlet and the 1-per-30-to-40-ft rule — and recommends the larger, safer count.Gutter sections & materials calculatorTurn gutter linear feet into a parts list: 10-ft sections, hangers, end caps, corners and downspout elbows, with the formula and a worked example.Gutter slope calculatorHow much slope should a gutter have? Enter the run length and pitch to get the total drop in inches, with the ¼-to-½-inch-per-10-feet rule and a worked example.Roof-pitch drainage-area calculatorConvert a roof footprint into the effective drainage area for gutter sizing. Enter footprint and pitch to apply the SMACNA pitch multiplier.Gutter capacity / flow referenceHow much roof can a 5-inch or 6-inch gutter drain? Set the rainfall intensity to see the max roof area per gutter size, K-style and half-round.

Gutter Cost Estimators

Budget the job: gutter installation cost, cost per linear foot, new-gutter / replacement cost, seamless gutter cost, labor cost, cost by material, and a contractor quote check — on the prices you enter from your own quotes.

Gutter installation costEstimate gutter installation cost from your prices: linear feet, downspouts, labor, add-ons and contingency. See the formula, worked example and labeled bands.Gutter cost per linear footWork out gutter cost per linear foot from your quote: linear feet times your dollars per foot, with labeled installed bands by material as a sanity check.New gutters / replacement costEstimate new-gutter or replacement cost: tear-off plus new gutter, downspouts, labor and contingency, all from the prices you enter. Formula and worked example.Seamless gutter costEstimate seamless gutter cost from your price per linear foot: one continuous run per eave, fewer leak points, plus downspouts and a contingency buffer.Gutter labor costEstimate gutter labor cost two ways: linear feet times your labor rate per foot, or crew hours times your hourly rate. Formula, worked example and FAQ.Gutter cost by materialEstimate gutter cost by material — vinyl, aluminum, steel, copper or zinc — from your price per foot, with labeled installed bands as a sanity guide.Gutter contractor quote checkCheck a gutter contractor quote: divide the total by your linear feet to get dollars per foot, then compare it against the labeled band for the material.

Gutter Guards & Leaf Protection

The leaf-protection cluster: gutter guard cost, leaf-guard / leaf-filter cost, guard quantity (linear feet & panels), guard cost by type (screen / foam / brush / micro-mesh / reverse-curve), and a DIY vs pro compare.

Gutter guard costEstimate gutter guard cost from your own price per foot, labor and contingency. Enter linear feet, get a planning total with the formula and a worked example.Leaf-guard / leaf-filter costEstimate reverse-curve leaf guard and leaf filter cost from your price per foot plus contingency. See the labeled $15-30/ft band, the formula and an example.Gutter guard quantity calculatorHow many gutter guard panels to buy: guard linear feet equals your gutter run; panels are linear feet divided by panel length, rounded up, with an example.Gutter guard cost by typeCompare gutter guard cost by type - screen, foam, brush, micro-mesh and reverse-curve - from your own price per foot, with labeled installed bands.DIY vs pro gutter guardCompare DIY versus pro gutter guard cost from your own prices: material-only DIY against installed plus labor, with the dollar gap and an example.

Downspouts & Drainage

Get the water down and away: downspout count & sizing, downspout extension / discharge distance, elbows & offsets quantity, rainwater volume from the roof, and downspout cost — stopping at the discharge point 4–6 ft from the wall.

Downspout count & sizing calculatorHow many downspouts does a roof need? Size by drainage area and the 30–40 ft spacing rule, and pick a 2×3, 3×4 or round outlet. Free, with a worked example.Downspout extension calculatorCount the extension pieces that discharge roof water 4–6 ft from the foundation. Free downspout calculator with the formula and a worked example.Downspout elbows & offsets calculatorCount downspout elbows and offset fittings: 2 top plus 1 bottom per downspout, and 2 per soffit offset. Free calculator with the formula and a worked example.Rainwater volume calculatorHow many gallons does a roof shed per inch of rain? Footprint × 0.6234 × runoff. Free rainwater calculator with the formula and a worked example.Downspout costEstimate downspout cost from your own prices: pipe per foot plus elbows and fittings. Free calculator with the formula, a worked example and a labeled band.

Gutter Cleaning & Maintenance

Keep them flowing: gutter cleaning cost (by linear foot, stories and pitch), a cleaning frequency reference, gutter repair cost, and a cleaning cost by home size.

Gutter cleaning costEstimate gutter cleaning cost from the linear feet, your price per foot, and labeled story and pitch multipliers. Worked example, formula, and FAQ inside.Gutter cleaning frequency referenceHow often to clean your gutters, by tree cover. A labeled reference: once a year with no trees, twice with some, three to four times under heavy pine and oak.Gutter repair costEstimate gutter repair cost from your own prices: reseal joints, rehang sagging runs, fix a downspout, add a contingency. Formula and worked example inside.Gutter cleaning cost by home sizeEstimate gutter cleaning cost from your home footprint. Length and width become an upper-bound perimeter, then your price and story factor set the total.

Materials & Types

Compare and choose: material cost & lifespan (aluminum / copper / steel / vinyl), K-style vs half-round capacity, 5" vs 6" capacity, seamless vs sectional, and a gutter gauge / thickness reference.

Material cost & lifespan compareCompare aluminum, copper and vinyl gutters on installed cost and cost per year over their service life, from your own prices and labeled lifespan bands.K-style vs half-round capacitySee the smallest K-style and smallest half-round gutter that drains your effective roof area at a given rainfall intensity, with a labeled capacity table.5" vs 6" gutter capacityCompare 5-inch and 6-inch K-style gutter capacity at your rainfall intensity and see the extra cost of stepping up to 6-inch over your linear feet.Seamless vs sectional compareCompare seamless and sectional gutters on section count, leak-prone joints and installed cost from your own per-foot prices, over any run length.Gutter gauge / thickness referenceLook up aluminum gutter gauges — economy .019, standard .027 and heavy .032 inch — and where each thickness makes sense for runs and snow load.
Planning estimate: this is a planning estimate from the numbers you enter — not a bid or a contract. Gutter pricing depends on material, size, linear feet, guards, fascia condition, removal, height/access and local labor. Get itemized written quotes from licensed, insured gutter contractors before you commit.
Measure your eave runs and confirm capacity, spacing and coverage against the exact product you buy. Allow extra for corners, waste and slope (~5–10%). Sizes, capacities, spacings and panel lengths vary by product and brand — read the label and the manufacturer’s data.

The gutter-size drainage-area reference

Our own SMACNA-style reference: the maximum roof area each gutter size drains across the whole US rainfall-intensity range (2, 4, 6 and 8 in/hr) — one neutral drainage matrix instead of a dozen single-brand quote widgets. It powers the gutter size calculator; see how it’s built in the methodology.

Open the drainage-area reference →

Built for the whole gutter project — and to stay correct forever

GutterCalcs gathers the calculations homeowners, DIYers and small contractors reach for when gutters go up — how much guttering to buy (linear feet from the eave runs, 10-ft sections, hangers, end caps, corners, downspout elbows), how many downspouts a roof needs, what size gutters (5" vs 6", K-style vs half-round) the roof requires, and what a job costs — size → quantity → cost → guard/clean/material, in one focused hub, in US units, without signup, with transparent formulas. Every tool shows not just the answer but the underlying formula, a worked example and a reference table, so you can sanity-check a gutter contractor’s quote.

Because the tools rest on timeless drainage geometry (linear feet = Σ eave runs; effective roof area = footprint × pitch factor; the smallest gutter size whose drainage area ≥ that roof area; downspouts, sections and hangers by ceil; rainwater gallons = area × inches × 0.6234 × runoff; cost = quantity × your $/linear-foot + downspouts + labor + add-ons − discount, ×(1 + contingency)) and stable, labeled conventions (roof-pitch multipliers, US rainfall intensity, max roof drainage area per gutter size, downspout capacity, hanger spacing, cost bands), they stay correct with no maintenance — no live material or labor price list, no regional cost index, no product catalog, no contractor directory. Cost tools use the prices you enter from your own quotes and bills; labeled cost bands are only a sanity guide. More at Sources & formulas, Methodology and About.

Estimates, not bids. Every result is a planning estimate from your own prices, or a material-quantity / sizing guide — not a bid, an install procedure, or structural roof-load, roofing, code or stormwater-drainage design. Get itemized written quotes from licensed, insured gutter contractors; measure your eave runs and confirm capacity, spacing and coverage against the exact product; and allow a little extra (~5–10%) for corners, waste and slope.