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Chicken coop calculator

Enter your flock. Every result updates as you type, with the range from extension guidance and the figure we sized on.

Your flockInputs
Bird size
Winters
Housing
Adjust the price assumptions

Wide ranges on purpose. Prices vary by region and month. Put in what your local store charges.

Item (USD)LowHigh
Panel, per sheet
2 x 4 x 8, per board
Hardware cloth, per sq ft
Roofing, per sq ft
Hardware, per project
Paint or sealer, per project
Insulation, per sq ft
Coop floor--
Run--
Roost length--
Nest boxes--
Ventilation--
Materials estimate--

    Floor plan

    Drawn to scale, one grid square is one foot. Plum bars: roosts, 12 in apart. Yolk squares: nest boxes. Green mark: pop door. Dashed: run.

    How we got these numbers

      Pop door and people door

      None of the extension publications we read gives a fixed pop door size, so we do not invent one. Measure your largest hen and make the opening big enough for her to walk through without crouching. What the sources do agree on: fit a solid latch and close it every night before dark (University of Kentucky, ID-245). Hang people doors so they open outward (Oregon State, EC 1644).

      Materials estimate

      ItemQuantityRange
      Total, materials only--

      This is an estimate on average US prices, not a quote: verify at your local store. Assumptions: walls 4 ft high (4 ft for coops up to 32 sq ft, 6 ft walk-in above that), roof 15% larger than the floor, 10% extra panel material, framing at 16 to 24 in on center, a 6 ft high run with a 12 in buried apron and a mesh top. No tools, labor, delivery, foundation, feeders, waterers or tax.

      Email me the checklist

        Saved plans stay in this browser only. The page address also keeps your inputs, so you can bookmark or share it.

        Where the numbers come from

        Every per-hen figure in this calculator comes from published guidance by US university extension services. They do not all agree. Where they differ, the table shows the published range and the value CoopSizer sizes on, usually the upper end, because a coop that is a little big costs less than one that is too small.

        ItemPublished rangeWe size on (bantam / standard / large)Sources
        Coop floor, with a runBantam 1 to 3, standard 1.5 to 4, large 2 to 5 sq ft3 / 4 / 5Mississippi State, Virginia Tech, Utah State, Penn State, Kentucky ASC-241, Cornell CCE, extension.org, Georgia, Minnesota
        Coop floor, no outdoor accessBantam 4, standard 8 to 10, large 8 to 10 sq ft4 / 10 / 10Oregon State, Kentucky AEN-161
        RunBantam 4 to 8, standard 2 to 10, large 10 to 12 sq ft8 / 10 / 12Mississippi State, Virginia Tech, Kentucky ASC-241, Cornell CCE, extension.org, Kentucky AEN-161
        Roost5 to 10 in per bird6 / 8 / 10 inOregon State, Penn State, Utah State, Virginia Tech, UC Coop. Extension
        Roost height and spacing13 to 24 in high, 10 to 18 in apart18 to 24 in high, 12 in apartPenn State, Oregon State, Kentucky ASC-241, Utah State
        Nest boxes1 per 5 hens to 2 for the first 4 plus 1 per 41 per 4, at least 2Minnesota, Utah State, Virginia Tech, Georgia, UC Coop. Extension, Maine, Kentucky ASC-241, Penn State, Oregon State
        Nest size12 x 12 x 12 in (12 to 15 in)12 x 12 x 12 inOregon State, Kentucky ASC-241, Penn State, Utah State
        Winter inlet6 sq in per 25 sq ft of floorsameKentucky AEN-161
        Ridge opening3 in per 10 ft of widthsameKentucky AEN-161
        Summer openingsAbout 18% of floor area as windowssameKentucky AEN-161
        Predator meshAbout 1/2 in hardware cloth or welded wire, not chicken wire1/2 in, run walls, apron and topKentucky AEN-161, UC Coop. Extension
        Buried apron6 in to at least 12 in12 inOregon State, Cornell CCE, Virginia Tech, Kentucky ID-245

        What this calculator does not do

        It does not check your local zoning, setbacks, flock limits or building permits. Many towns limit the number of hens, ban roosters, or require a permit or a minimum distance from neighbors. Check your local ordinances before building. It also does not size for meat birds, ducks or turkeys, which have different needs.

        Want the reasoning behind the numbers? Start with how much space chickens need, or see worked examples for 4 to 12 hens.

        Want these sizes drawn out? CoopSizer Plans turns them into dimensioned drawings, a materials list and a cut list, from $19.