Skip to main content
ACECALC

Gutter Calculator

Estimate gutter linear feet, downspouts, hangers, and elbows from your roof's eave length. Enter the total run, the number of separate runs, and building height to size the whole system.

Calculate Your Gutters & Downspouts

Updated July 2026 • Real local pricing via FRED PPI + state adjustments • Includes recommended waste factorsmethodology ↗

24 in OC is the standard warranty spacing; 16 in in heavy snow

Gutter Linear Feet
120
Downspouts
4
10 ft Sections
12
Hangers
60
Elbows
12
End Caps
4
Downspout Linear Feet
40
Estimated Material CostMedium confidence
$1,320
$11.00 per linear foot
Source ↗ · methodology
Create a professional quote from this estimate

Founding members get unlimited saves — $79/year (reg. $149). Price increases soon.

Estimates only. Always verify with your supplier before ordering.

How we calculate this

Every result is methodology-driven — never fabricated. We apply standard geometric formulas (length × width × depth, converted to the unit you order in) and then add a recommended waste factor for spillage, uneven ground, and offcuts.

For materials that settle — gravel, sand, base rock, and fill — the recommended waste factor doubles as your compaction allowance, so you order enough loose material to reach the finished depth after compacting. Cost figures pull from our regularly refreshed pricing dataset (FRED producer price indices plus state-level adjustments), not guesses.

See our full pricing methodology and sources for how every number is sourced and refreshed.

Pro feature — $79
Embed this calculator on your site →

How Do I Calculate How Much Gutter I Need?

Add up the length of every eave that needs a gutter — that linear footage is the amount of gutter to buy. Divide by 10 for the number of stock sections, then add one downspout per 30–40 feet of run, hangers every 24 inches, and two end caps per separate run. A typical single-story home with 120 feet of eave needs 12 ten-foot sections, about 4 downspouts, roughly 60 hangers, and 4 end caps across its two main runs.

Gutter estimating is driven by the eave — the horizontal bottom edge of the roof — not the roof area. Water sheets down the roof plane and collects at the eave, so every foot of eave over a walkway, doorway, or foundation gets a gutter. Rake edges (the sloped edges of a gable) don't get gutters. Measure only the horizontal runs.

Sections formula: Sections = eave length ÷ 10 ft, rounded up. Seamless aluminum is formed to your exact run length on site, so sections only matter when you buy sectional gutter in pre-cut 10-foot lengths.

How Many Downspouts Do I Need?

One downspout drains about 30–40 linear feet of gutter, so most homes need a downspout every 35 feet or so. A 120-foot eave works out to 4 downspouts. Two cross-checks keep you honest: one downspout handles roughly 600–800 square feet of roof area, and no single slope run should exceed 40 feet without draining to a downspout at each end. Undersizing downspouts is the number-one cause of gutters overflowing in a hard rain — when in doubt, add one.

How Far Apart Should Gutter Hangers Be?

24 inches on center is the standard, and the spacing most manufacturers require to honor their warranty. Hidden hangers screwed into the fascia every two feet keep the gutter from sagging under the weight of water and debris. In heavy-snow climates, tighten to 16 inches on center — an ice-loaded gutter can weigh several pounds per foot. A 120-foot run at 24 inches on center needs about 60 hangers.

How Many Elbows and End Caps?

Budget three elbows per downspout and two end caps per separate gutter run. The two top elbows offset the downspout back to the wall from the gutter outlet; the bottom elbow kicks water away from the foundation. End caps close the open ends of each run — a run that starts and ends in the open needs two. Where gutters wrap a corner of the house, add an inside or outside miter (corner) at each turn.

5-Inch vs. 6-Inch Gutters

5-inch K-style is the residential default; 6-inch K-style carries about 40% more water for large or steep roofs and high-rainfall climates. Match the downspout to the gutter — 2×3-inch downspouts on 5-inch gutter, 3×4-inch on 6-inch. Stepping up to 6-inch doesn't change the linear footage or downspout count from this calculator; it just changes the profile you order and lets each downspout drain more roof.

Which Gutter Material Should I Use?

  • Seamless aluminum: The most common choice — rust-proof, affordable, and roll-formed on site so there are no seams to leak. Pro install.
  • Vinyl: Cheapest and DIY-friendly (snap-together 10-ft sections), but gets brittle in cold and sags over long runs.
  • Galvanized / stainless steel: Heavier-duty for snow and falling-branch country; steel resists denting better than aluminum.
  • Copper: Premium at 4–6× aluminum cost, with a 50+ year life and a living patina finish. Soldered seams, pro install only.

Common Eave Lengths — Gutter Estimates

Pre-calculated for a single-story home, 24-inch hangers, one downspout per 35 feet:

  • 80 ft eave — 8 sections, 3 downspouts, ~40 hangers
  • 120 ft eave — 12 sections, 4 downspouts, ~60 hangers
  • 160 ft eave — 16 sections, 5 downspouts, ~80 hangers
  • 200 ft eave — 20 sections, 6 downspouts, ~100 hangers

Cost varies by region. The Estimated Material Cost card pulls from our indicative national-average pricing dataset (refreshed quarterly). Northeast and California metros run 15–40% above the national midpoint while Midwest and Southeast metros run 5–15% below — verify locally for binding quotes.

Related Calculators

Written by Daniel McCarney — AceCalc