Chicken Coop Size Calculator
Enter your flock size to get coop floor space, nest boxes and roost length, using Penn State and Oregon State Extension figures.
Where these numbers come from
- Coop floor: Penn State Extension lists 1.5 sq ft per laying hen, 2 sq ft per large chicken and 1 sq ft per bantam inside the coop. Oregon State University Extension recommends a roomier 3 sq ft per bird when birds also have a run, and 8 to 10 sq ft per bird when the coop is their only space. The calculator shows the range between the two and sizes the coop to the roomier figure.
- Nest boxes: at least 12 x 12 x 12 in, two for the first four hens and one more for every four after that, at least 2 ft off the ground.
- Roosts: 5-10 in of perch per standard bird at 18-24 in off the floor, or 4 in per bantam at 12-18 in. Space multiple perches about 10 in apart and keep them under about 4 ft high.
- Run: extension guides don't give one number for runs. Our rule of thumb is to give run birds at least the 8-10 sq ft per bird that Oregon State sets for birds that never go outside, and more if you can.
Read the full guide: Building a Backyard Chicken Coop: Space, Nest Boxes & Predator-Proofing.
Build it from a plan
The Homestead Chicken Coop Build Guide walks through a predator-proof coop step by step, and the Chicken Flock Record Book keeps egg counts, feed and health in one place.
See the coop build guide →Common questions
How big should a coop be for 6 chickens?
For six laying hens that also have a run, plan 9 to 18 sq ft of coop floor: Penn State's 1.5 sq ft per hen at the small end and Oregon State's 3 sq ft per bird at the roomy end. A 4 x 6 ft coop fits the roomier figure, with three nest boxes and 2.5-5 ft of roost.
How many nest boxes do I need?
Two boxes for the first four hens, then one more for every four hens after that. Hens share boxes happily, so you don't need one per bird.
How much roost space does a chicken need?
About 5-10 in of perch per standard bird and 4 in per bantam. Set perches 18-24 in off the floor for standard breeds, about 10 in apart, and no higher than about 4 ft.