How to use the chicken feed calculator
- Enter the number of chickens and how much each eats per day (1/4 lb is a good default for full-size layers).
- Enter your feed bag size and the price per bag.
- Enter the average eggs per hen per week to see your cost per dozen.
- Optionally add other monthly costs such as bedding, grit, oyster shell and treats.
The formulas
Feed per day = chickens × feed per bird Bag lasts = bag size ÷ feed per day Monthly cost = feed per day × 30.44 ÷ bag size × bag price (+ other costs) Cost per dozen = monthly cost ÷ (hens × eggs per week × 30.44 ÷ 7 ÷ 12)
Worked example
Six hens, 1/4 lb of feed each per day, $22 for a 50 lb bag, 5 eggs per hen per week:
- Feed per day = 6 × 0.25 = 1.5 lb
- A bag lasts 50 ÷ 1.5 = 33 days; you need 11 bags a year
- Monthly feed cost ≈ $20.09
- Eggs per month ≈ 130 (10.9 dozen), so feed costs about $1.85 per dozen
How much chickens eat
| Bird | Feed per day | Feed type |
|---|---|---|
| Chicks, 0–6 weeks | rising to about 1.5–2 oz (40–55 g) | Chick starter |
| Pullets, 6–18 weeks | 2.5–4 oz (70–115 g) | Grower |
| Laying hen, full size | about 4 oz / 1/4 lb (115 g) | Layer feed + oyster shell |
| Bantam hen | about 2 oz (55 g) | Layer feed |
| Meat birds (broilers) | much more — follow the feed supplier's chart | Broiler starter / finisher |
These are typical figures. Breed, size, weather, forage and how much feed is spilled all change real-world intake, so the most accurate number is your own: note the date you open a bag and the date it runs out.
Tips to save on feed
- Stop spillage: hang the feeder at the height of the birds' backs and fill it only partly. Hens flick a lot of feed out of low, full troughs.
- Keep pests out: rodents and wild birds can eat a surprising amount. Use a treadle feeder or bring feed in at night, and store bags in metal bins.
- Buy in bulk if you can use it while it is fresh — feed is best within about three months of milling.
- Let them forage: supervised free-ranging reduces feed use, though egg yolks and laying rates vary with the season.
- Fermented feed is popular with some keepers to reduce waste; keep it clean and discard anything that smells off.
Egg production through the year
Hens lay best with about 14–16 hours of daylight, so production falls in winter, during the yearly molt and as hens get older — most lay well for two to three years. A hen that lays 5 eggs a week in summer may lay 2 or none in midwinter, while still eating the same amount of feed. For a realistic yearly cost per dozen, use an average of about 3–4 eggs per hen per week for a mixed-age flock.