Rabbit cage size calculator
Size a hutch before you buy the wire: three medium rabbits of 2 to 4 kg need at least 9 square feet of floor, 3 each, and the cage must be 14 inches high inside. Built on the official per-rabbit table. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Rabbits
- 3
- Weight class
- Medium
- Weight range
- 2–4 kg (4.4–8.8 lb)
- Sq ft per rabbit
- 3
- Area sqft
- 9
- Area sqm
- 0.83612736
A rabbit cage is too small when the floor cannot hold the animals that live on it. Breeders, 4-H exhibitors, laboratory animal programs, and house-rabbit keepers all look up a rabbit cage size number for the same reason: they need the minimum floor area in square feet before they buy wire, build a hutch, or pass an inspection. This calculator takes two inputs only — how many rabbits share the enclosure, and which USDA weight class those rabbits fall into — and multiplies the official per-animal allotment from 9 CFR 3.53 by the head count. Small rabbits under two kilograms need one and a half square feet each; medium rabbits from two to four kilograms need three; large rabbits from four to five point four kilograms need four; giant rabbits above that need five.
What USDA 9 CFR 3.53 allots per rabbit and how the floor adds up
Minimum rabbit cage floor area is not a furniture dimension and it is not a guess from a pet-store aisle. The United States Department of Agriculture publishes a table in 9 CFR 3.53 that assigns a minimum floor area, in square feet, to each rabbit according to its live weight class, and then requires that space for every animal in the primary enclosure. This rabbit cage size calculator implements that table exactly.
A small rabbit that weighs less than two kilograms, about four point four pounds, is allotted one and a half square feet. A medium rabbit from two to four kilograms, about four point four to eight point eight pounds, is allotted three square feet. A large rabbit from four to five point four kilograms, about eight point eight to eleven point nine pounds, is allotted four square feet.
A giant rabbit above five point four kilograms is allotted five square feet. The required floor area for a group is the per-rabbit allotment multiplied by the head count, because the regulation states the space for each rabbit rather than a shared lump that shrinks as more animals arrive. Interior height must still be at least fourteen inches; that height is reported so a builder does not meet the floor area and then fail the height clause.
The identity is deterministic: three medium rabbits always require nine square feet. Pet-welfare groups often recommend larger playpens than this laboratory and commercial minimum; this page reports the regulatory floor, not a luxury condo, so an inspector and a spreadsheet can agree on the same number.
Where a rabbit cage size calculator earns its keep
Hutch builders, 4-H leaders, commercial rabbitries, and laboratory animal programs look up a rabbit cage size calculator because they need square feet from a head count and a weight class, not a generic room-area tool and not a dog-crate chart. A bed-size page answers how much floor a mattress occupies. A potting-soil page answers litres of mix.
A dog-food page answers cups from body weight. None of those searches is how large a cage three Californians need before the next inspection. Breeders use it to size a new battery before they cut wire.
Teachers use it so students can check the USDA table without flipping a row by hand. Rescue groups use it to reject a donated hutch that looks roomy in a photograph and then fails the floor test once the rabbits are counted. Automation scripts that plan a barn renovation or that fill a permit worksheet need a deterministic oracle, not a screenshot of a faded extension leaflet.
This page is not a rabbit-age human-year converter and it is not a pet-sitter rate card. Invalid counts do not consume balance.
What you can do with it
Hutch and wire buy list
Enter how many rabbits will share a new hutch and their USDA weight class to get the minimum floor area in square feet before you cut wire or order a cage.
Classroom USDA table check
Let students submit a positive integer head count and a weight class and verify that the product matches the published per-rabbit allotment without a rounding argument.
FAQ
What are the rabbit weight classes?
small is under 2 kg (1.5 sq ft each), medium is 2 to 4 kg (3.0 sq ft), large is 4 to 5.4 kg (4.0 sq ft), and giant is over 5.4 kg (5.0 sq ft). Pick the class of the heaviest rabbit in the enclosure.
What happens if the rabbit count is not a positive integer?
Zero, negative numbers, fractions, and non-numeric values are rejected and are not billed, because a cage cannot hold a non-integer rabbit.
Is this the same as a house-rabbit playpen recommendation?
No. The result is the USDA 9 CFR 3.53 individual minimum floor area plus the fourteen-inch interior-height floor. Many pet-welfare groups recommend a larger exercise pen; this calculator reports the regulatory floor.
How tall does a rabbit cage need to be?
At least 14 inches of interior height, whatever the floor area. The height is shown next to the result so a cage that meets the floor rule does not fail on the height rule at inspection.
Do several rabbits share one space allotment?
No. The allotment is per rabbit, so it is multiplied by the head count. Three medium rabbits need 9 square feet, three times the 3 square feet one medium rabbit needs on its own.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/bio/rabbit-cage-size \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"rabbits":3,"weight_class":"medium"}'const res = await fetch("https://api.kit.forhosting.com/bio/rabbit-cage-size", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"rabbits": 3,
"weight_class": "medium"
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/bio/rabbit-cage-size",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"rabbits": 3,
"weight_class": "medium"
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/bio/rabbit-cage-size", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"rabbits":3,"weight_class":"medium"}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"rabbits":3,"weight_class":"medium"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/bio/rabbit-cage-size", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"rabbits": 3,
"weight_class": "medium"
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "bio.rabbit_cage_size",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Limits
max_rabbits | 500 |
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
A count that is not a positive integer is rejected as invalid_input instead of inventing an area.
Input contract, response shape, and error behaviour
Example: three medium rabbits yield nine square feet, because each medium rabbit is allotted three square feet. Failed validation is not billed. The same two-field contract is what the free browser form posts, so a check you type by hand matches an automation call on the same count and class. POST a JSON body with two required fields: rabbits, a positive integer head count no greater than five hundred, and weight_class, one of the closed labels small, medium, large, or giant. The count may arrive as a JSON integer or as a whole-number string; fractions, zero, negatives, empty strings, and missing keys fail with invalid_input naming rabbits and stating that a positive integer is required. weight_class is an enum, not free text, so the form can render a select instead of asking a visitor to memorise kilogram bands. Aliases rabbits accepts include count, n, and rabbit_count; weight_class accepts class, size, and weight_band. On success the body echoes rabbits and weight_class, reports the live-weight band that selected the row, the per-rabbit allotment in square feet, the required floor area in square feet and in square metres using the exact international-foot conversion, and the fourteen-inch interior-height floor. The formula field restates the product; formula_applied substitutes the numbers so a worksheet can print the arithmetic next to the answer. Pair the area with your own drawing if you need a sketch of a hutch; this endpoint computes floor area only and does not emit wire-gauge charts, nest-box volumes, or doe-with-litter extras.
Where a rabbit cage size calculator earns its keep
Pin area_sqft in tests, keep the head count a positive integer, pick the weight class that matches the heaviest rabbit in the group, and you get the same nine square feet for three medium rabbits in a lecture notebook, an LMS plugin, and a barn spreadsheet.
Integration use cases
4-H and inspection worksheets
Check a standing enclosure against 9 CFR 3.53 by counting the rabbits, selecting the heaviest weight class in the group, and comparing the returned area_sqft to the measured floor.
Technical questions
How do I calculate rabbit cage size from count and weight class?
Send rabbits as a positive integer and weight_class as small, medium, large, or giant. The API returns area_sqft equal to the head count times the USDA 9 CFR 3.53 allotment for that class (1.5, 3, 4, or 5 square feet per rabbit).
What does the rabbit cage size calculator cost?
The browser tool is free. API requests use prepaid KIT balance at $0.002 per successful call; invalid input is not billed.