Feed Conversion Ratio Calculator

How to use this calculator

1. Use feed consumed and production recorded over the same period and group.
2. For live-weight gain, enter both beginning and final group weights. For milk or eggs, the output field is the period total.
3. Add a feed price and target production quantity to estimate the feed requirement if the same conversion holds.

Formula and method

For the assumptions behind these results, read the explanation below. You can also explore Animal Mortality Rate and Grain Bin.

Match the input and output basis

Feed conversion is meaningful only when the quantities describe the same animals and interval. For a group, use the total group gain rather than one animal’s gain. Keep the feed basis consistent as well: dry-matter intake and as-fed intake are different measures, especially when moisture varies among rations.

Milk and egg production need a clearly stated output unit. This implementation uses kilograms of milk and reports egg conversion per dozen, while the target field still asks for an egg count. A ratio from one production type cannot be compared numerically with a ratio based on another output.

Efficiency is not the whole economic picture

Lower feed per unit of comparable output generally indicates better conversion, but it does not automatically imply greater profit or better welfare. Feed price, growth time, health, mortality, product quality, and overhead all affect the economics. The cost projection here covers feed only.

The projection assumes the measured conversion remains constant for the target. In practice, growth stage, temperature, genetics, ration changes, and measurement error can shift conversion. Record feed wastage separately where possible: feed delivered is not necessarily feed consumed. Avoid interpreting a ratio based on tiny or negative gain as a stable prediction.

Evidence and assumptions

Dairy reports often use energy-corrected milk divided by dry-matter intake. This tool’s milk mode uses the opposite orientation—feed divided by milk—and does not correct milk for fat or protein. Compare it only with records on the same feed and output basis; do not apply published energy-corrected milk-to-feed benchmarks to this output.