Free tool
Brooder Size Calculator
How big a brooder, what heat plate, and what temperature your chicks need this week. Enter the count and their age and it works out all three, from the standard brooding figures.
Brooder floor
5 sq ft
minimum for this week, more is better
Temperature under the plate
95°F
about 35°C
Chicks start at about 95°F under the plate in week one, and you lower it roughly 5°F a week by raising the plate on its legs, until it matches the coop and they can move out, usually around week six. Watch the chicks, not just the number: huddled together and cheeping means too cold, spread to the edges and panting means too hot. A heat plate they huddle under is the safe choice here, not a heat lamp, which is a leading cause of coop fires.
Space grows with the chicks
Day-old chicks take up almost no room, so a small brooder feels roomy in week one and cramped by week four. Start at about half a square foot each and plan for roughly one square foot a chick by the time they are feathering out, and give more if you can: a crowded brooder is where pecking and pasty vent problems start. A large plastic tote works for a few chicks; a stock tank or a sectioned-off area suits a bigger batch.
The temperature ladder
The old rule is 95°F under the heat in week one, dropping about 5°F a week until the chicks are fully feathered and the brooder matches the coop, usually around week six. With a heat plate you do that by raising it on its legs rather than by swapping bulbs. The better guide is the chicks themselves: a warm pile in the middle means turn it up, birds pressed to the cool corners means turn it down.
Plate, not lamp
The single most important brooder decision is the heat source, and the answer is a radiant heat plate, not a heat lamp. A lamp is a leading cause of brooder and coop fires and heats the whole box; a plate the chicks duck under stays cool to the touch and lets them self-regulate. We work through why in the heat plate versus heat lamp guide.
The brooder kit
Warmth is the one thing to get right. A heat plate the chicks huddle under, and a feeder that carries over to the coop.
RentACoop
RentACoop 12x12 Chick Brooder Heat Plate
The heat source the calculator sizes for. Chicks huddle under a radiant plate that stays cool to the touch, and you raise it on its legs to lower the temperature each week. The safe replacement for the fire-prone heat lamp.
Brinsea
Brinsea EcoGlow Safety 600 Brooder
The premium heat plate, with a well-earned safety reputation for brooding chicks and ducklings. Height-adjustable like the RentACoop and a step up in build; worth it if you brood every year or want the extra margin.
Harris Farms
Harris Farms Galvanized Feeder
Chicks need chick starter in front of them at all times. A galvanized feeder keeps that feed clean in the brooder and carries straight over to the coop once the flock moves out, so it is not a single-use buy.
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