Put in your flock and see what the people who sell the chicks say it should give you — each hatchery’s own figure, not an average of them — plus what today’s day length and your hens’ ages do to that number, and how many hens it takes to keep a dozen eggs a week on the counter.
24–36 eggs a week
What each source publishes, for your flock
A hen that stops laying suddenly, or lays soft or shell-less eggs for more than a few days, is a question for a vet rather than for a calculator — and so is any bird that is off her food or sitting fluffed up.
Laying rules checked 2026-09-22; hatchery figures 2026-09-22.
Quick answer: a hen in her first laying year gives roughly six eggs a week at her best, which is what the University of Minnesota Extension publishes for hens in general — so six hens is about three dozen a week in summer. But the hatcheries’ own figures for the same breed differ by eighty eggs a year, laying falls every year after the first two, and short winter days stop it almost completely unless you add light. This calculator shows each source’s figure for your flock, and says which way reality moves from it.
What the numbers mean
Every figure here is somebody’s published estimate for a hen in her first laying year, in good conditions. Cackle Hatchery prints ranges (“200 to 280 a year” for a Rhode Island Red) and labels them estimates. McMurray Hatchery prints a single average (238 for the same bird). Meyer Hatchery prints a rate — 4 to 6 eggs a week — and never converts it to a year. The Livestock Conservancy prints a rate of lay for the heritage breeds.
This tool keeps them apart. It never multiplies a weekly figure into a year, because hens molt and rest and nobody published what that adds up to; and when it divides a yearly figure into a week, it says out loud that this is an average across the whole year, midwinter and molt included. That is why the weekly answer and the yearly answer here do not line up — they are answers to different questions.
The two things that change it, and nobody quantifies
Age. The University of Minnesota: hens begin laying at around six months and can continue for five to ten years, “with peak production occurring in the first two years”. The University of Wisconsin: “the level of egg production, egg size, and shell quality decrease each year.” Penn State says the same. Not one of them publishes a percentage, so this calculator does not invent one: pick your flock’s age and it tells you where you are on that curve in words, not in a number somebody made up.
Daylight. This one the tool can compute, because day length is astronomy. Give it your rough latitude and it works out how long today is, then compares that with the published thresholds — which disagree: the University of Minnesota says hens need at least 12 to 14 hours of light to keep laying, the University of Wisconsin says maximum production comes at 16 hours and 14 to 16 keeps it going. At 45° north in late December the day is under nine hours, which is well under either figure. Minnesota adds the practical note: a regular light bulb is enough to make up the difference.
Molt: the autumn cliff
If your hens stop in September or October and you have not changed anything, it is almost certainly the molt. Mississippi State Extension: “Each year chickens molt, or lose the older feathers, and grow new ones. Most hens stop producing eggs until after the molt is completed.” A late-molting hen — usually the better layer — sheds fast and is back in 2 to 3 months; an early molter can take 4 to 6. Feathers are mostly protein, so this is the one time of year a bit of extra protein genuinely helps.
How many hens do I need?
Work backwards from the weekly figure: for a dozen eggs a week you need about two or three hens of a good laying breed in their first year, or more of a heritage breed that lays 150 a year. Then add one, because a broody hen, a molt or a fox takes a bird out of the count at exactly the moment you were counting on her. The calculator does the arithmetic from whichever figure your breed has.