Why Backyard Egg Economics Matter
Raising hens for home egg production is often portrayed as a wholesome hobby that pays for itself, but the math can be surprisingly complex. Feed, bedding, and the initial coop investment add up quickly, while egg output fluctuates with age and season. This calculator helps demystify the finances by converting all major costs into a cost per dozen eggs. By comparing this figure with the going store price, you can see whether the endeavor is saving money or simply providing entertainment and fresher breakfasts.
Many online discussions rely on anecdotes or ignore depreciation of the coop. By amortizing the capital cost over its useful life, the tool reveals a more accurate break-even point. It also uses a straightforward model of annual egg production per hen so you can adjust the assumptions for your breed or climate. While simplifying assumptions are necessary, the approach is transparent so you can adapt the inputs to your situation.
The fundamental formula is expressed in MathML below. Annual feed cost is converted to an annual figure and added to the amortized coop cost. That total is then divided by the number of dozens produced per year:
Where C is the cost per dozen, F is the monthly feed cost, K is the coop cost, Y is the years of amortization, H is the number of hens, and E is the eggs each hen lays per year. The formula in MathML clarifies that the coop cost is spread evenly across its lifespan and the egg output is converted from individual eggs to dozens.
Worked Example
Imagine a family keeps four hens, spending $25 per month on feed. The coop and basic equipment cost $600 and are expected to last ten years. Each hen reliably lays about 250 eggs per year. Plugging these values into the calculator, annual feed cost becomes $300. The coop amortization is $60 per year. Total cost is thus $360. Egg production is 1,000 eggs, or 83.3 dozens. The resulting cost per dozen is roughly $4.32. If the store sells eggs for $3.50, home production is more expensive by $0.82 per dozen under these assumptions. Yet if local organic eggs cost $5, the backyard project is financially worthwhile even before accounting for freshness and the entertainment value of the flock.
Scenario Comparisons
| Scenario | Hens | Cost per Dozen ($) |
|---|---|---|
| Small Flock | 3 | 5.10 |
| Medium Flock | 6 | 3.60 |
| Large Flock | 10 | 3.00 |
The table illustrates how scale affects cost per dozen. Larger flocks spread the coop cost across more eggs, driving the price down. The relationship is not limitless—feed costs rise proportionally with flock size—but hobbyists often discover that adding a few more hens meaningfully lowers the cost per egg.
How to Use This Tool
Enter the number of hens and your monthly feed expenditure. Include any supplements or grit in the feed cost for accuracy. For the coop and equipment cost, add up the purchase price of the coop, nesting boxes, feeders, and waterers. Amortize these costs over the number of years you expect to keep the flock. Egg production per hen per year varies by breed and daylight hours, so adjust the default 250 figure accordingly. Finally, compare your cost per dozen with the store price in your area to gauge the financial trade-off.
Limitations and Assumptions
This model assumes hens lay uniformly throughout the year and that feed cost is constant. It does not include labor, veterinary care, or unexpected losses from predators and disease. Molting seasons, extreme weather, or aging hens will reduce egg output, raising the cost per dozen. The calculator also assumes that the coop remains functional without significant additional investment. Use the results as a baseline rather than a precise forecast, and revisit the numbers periodically as circumstances change.
Related Tools
Planning to expand your flock? Use the chicken coop space planner to make sure your birds have adequate room. To estimate seasonal output, check the egg production calculator for breed-specific laying patterns.