How much feed do chickens eat? The monthly maths for 4, 6 and 12 hens

Ali Rizwan — Mon, 02 Nov 2026 09:56:15 +0000

One of the first questions new chicken keepers ask is deceptively simple: how much feed will I actually go through?

The planning number most keepers use is about 1/4 lb (roughly 115 g) of feed per laying hen per day. Scale that up and the monthly picture looks like this:

4 hens: ~1 lb a day → ~30 lb a month
6 hens: ~1.5 lb a day → ~45 lb a month (about one standard 40–50 lb bag)
12 hens: ~3 lb a day → ~90 lb a month

That one number drives two useful things. First, your feed budget: multiply bags per month by your local bag price and you have your real monthly cost. Second, it feeds straight into your cost per egg — divide monthly feed cost by the dozens you collect and 'free' backyard eggs get an honest price tag (for a lot of small flocks it lands around $2–4 a dozen, feed being most of it).

I built free calculators that do this maths for any flock size, in lb or kg:

Chicken feed calculator: https://flockcalc.site/chicken-feed-calculator
Cost per egg calculator: https://flockcalc.site/cost-per-egg-calculator
All the flock calculators: https://flockcalc.site

If your flock eats noticeably more or less than the 1/4 lb rule, I'd love to hear what breed and setup you're running — real numbers from real coops are what make tools like this better.

I built a free calculator site for backyard chicken keepers — here's what I learned about coop maths

Ali Rizwan — Sun, 01 Nov 2026 20:19:19 +0000

I recently shipped FlockCalc, a small site of free calculators for people who keep chickens, quail and ducks in their backyard. No accounts, no ads — just instant answers.

The interesting part wasn't the code, it was the maths arguments. Ask ten chicken keepers how much coop space a hen needs and you get ten answers. I ended up using the university extension figures: about 3.5 sq ft of coop and 10 sq ft of run for a standard hen, 2/6 for bantams, 4.5/12 for large breeds, 10 inches of roost per bird, and one nesting box per four hens.

That means the classic 4 × 8 ft coop honestly holds about 9 standard hens — not the 16–20 the box claims.

The most-used tool so far is the chicken coop size calculator. The one that surprised me is the cost per egg calculator: six hens on a $25 feed bag work out to roughly $0.22 an egg, which is cheaper than most people guess — until you add housing, then it isn't.

There are 14 calculators now (feed, hatch dates, brooders, quail cages, duck houses) plus a few written guides. Built with Next.js as fully static pages, so hosting is free and every page loads instantly.

If you keep birds, I'd love to know which number you'd argue with first.

DEV Community: Ali Rizwan

How much feed do chickens eat? The monthly maths for 4, 6 and 12 hens

I built a free calculator site for backyard chicken keepers — here's what I learned about coop maths