Chicken Coop Size Calculator
Enter your flock size and bird type to see the coop, run, and nesting-box space you need.
Interior coop space24 sq ft
Outdoor run space60 sq ft
Nesting boxes2
Rule of thumb
4 sq ft indoor + 8–10 sq ft run per standard bird, and one nesting box per 3–4 hens.
Square feet per chicken by bird size
Space needs scale with the bird. Bantams are content with roughly half what a standard hen needs, while heavy breeds like Brahmas, Jersey Giants, and Orpingtons need noticeably more than the usual 4 sq ft figure. Roosting bar length matters too — birds sleep shoulder to shoulder on the bar, and running short of perch space causes squabbles at dusk.
- Bantams — 2 sq ft coop, 4–5 sq ft run, 6 in of roost per bird
- Standard laying hens (Leghorn, Australorp, Rhode Island Red) — 4 sq ft coop, 8–10 sq ft run, 8–10 in of roost
- Heavy breeds (Brahma, Jersey Giant, Orpington) — 5–6 sq ft coop, 12–15 sq ft run, 12 in of roost
Birds that free-range during the day can live with the lower end of the run figures, since the run is only their morning-and-evening space. Birds permanently confined to the run should get the high end or more. Crowding is the single most common cause of feather-picking, bullying, and disease in a backyard flock, so when you are between two coop sizes, buy the bigger one — you will almost certainly add birds later (see the chicken math calculator for how that goes).
How big should a coop be for 4, 6, or 12 chickens?
For standard hens at 4 sq ft each: 4 chickens need about 16 sq ft of coop (a 4×4 ft footprint) and a 32–40 sq ft run. 6 chickens need about 24 sq ft (4×6 ft) and a 48–60 sq ft run — this is the most common backyard flock size, and roughly what a family of four eats through; see how many chickens a family of 4 needs.12 chickens need about 48 sq ft (6×8 ft) and a 96–120 sq ft run. Add nesting boxes at one per 3–4 hens, so two boxes for six hens and three or four for a dozen — the nesting box calculator works this out exactly.
Keeping ducks instead? Ducks need more floor space than chickens — plan on about 5–6 sq ft each in the house — but they do not roost or use nesting boxes, so you can skip the perches and give them floor bedding instead.
How we calculate it
Indoor = birds × 4 sq ft (standard breed). Run = birds × 8 to 10 sq ft. Nesting boxes = 1 per 3 to 4 hens.
Based on:
- Indoor space guidelines run about 2 to 4 sq ft per standard bird (Poultry Extension)
- An outdoor run of about 5 to 10 sq ft per bird (Penn State Extension)
- General housing and space guidance for backyard flocks (UGA Extension)
Figures are typical guidelines for planning. Your birds, breed, climate, and feed will vary.
Frequently asked questions
How much space does a chicken need in a coop?
Standard-size hens need about 4 sq ft of interior coop space each, plus 8–10 sq ft each in an outdoor run. Bantams need less; large breeds like Brahmas need more.
How big should the run be?
Aim for at least 8–10 sq ft of run per standard bird. More is always better, since crowded runs lead to bullying, feather-picking, and disease.
How many nesting boxes do I need?
One nesting box per 3–4 hens is the standard rule. Hens tend to share favorite boxes, so you rarely need one each.