Chicken Coop Size Calculator
| Flock | Coop floor | Run | Nesting boxes |
|---|---|---|---|
| 4 hens | 16 sq ft | 40 sq ft | 1 |
| 6 hens | 24 sq ft | 60 sq ft | 2 |
| 12 hens | 48 sq ft | 120 sq ft | 3 |
Coop sizing is three rules per flock: four square feet of coop floor per standard bird, ten square feet of run per bird, and one nesting box for every four hens - the numbers that keep a backyard flock from turning into a pecking-order crisis by August.
Bottom line: six hens want a 24-square-foot coop with a 60-square-foot run and two nesting boxes - a 4-by-6 coop on an 8-by-8 run, which fits most suburban side yards. Bantams count as half a bird; heavy breeds like Orpingtons count as one and a quarter, because winter confinement is when undersized coops turn flocks mean.
The honest part: the rules are minimums for chickens that free-range daily, and the coop chickens stay in all winter need closer to six or eight square feet each - crowding is the root of feather-picking, egg-eating and every behavioral problem the chicken forums diagnose. Build one size up; the flock always grows.
How to use
- Enter your planned flock size and breed class - standard, bantam at half, or heavy breeds at 1.25 - and read the coop floor, run space and nesting boxes.
- Add the roost length: 8 to 12 inches of bar per bird, all at the same height or ladder-stepped, because the pecking order enforces the top roost.
- Check the result against the winter reality: if the flock stays confined for weeks at a time, size to six square feet inside per bird instead of four.
Frequently asked questions
How big should a coop be for 6 chickens?
Twenty-four square feet of coop floor - a 4-by-6 - with a 60-square-foot run and two nesting boxes for six standard hens. Add 8 to 12 feet of roost bar at the same or stepped heights, and if the flock winters confined, the honest build is a 4-by-9 with the extra floor for the weeks nobody wants to walk on snow.
How many nesting boxes per chicken?
One box per four hens - chickens share, they lay on a schedule rather than simultaneously, and extra boxes just collectone hen claiming two. Twelve hens want three boxes; even a six-hen flock is fine with two. The boxes go lower than the roosts, dark-ish, and never under where the roosting happens, for reasons the coop floor makes obvious.
How much run space do backyard chickens need?
Ten square feet per standard bird in the run is the crowded-but-working minimum with daily free-ranging; twenty per bird is where a run stays green instead of becoming a dirt paddock. Bantams halve it, and the run's fence matters as much as its size - a 10-square-foot run a hawk can reach into is not a run.
Do bantams and standard breeds need different coop sizes?
Bantams count as roughly half a standard bird - two per four square feet - while heavy breeds like Orpingtons and Cochins run about a quarter larger. Mixed flocks size to the biggest birds, and the roost spacing sized for Orpingtons lets the bantams tuck into the gaps the big birds leave.