Feed Conversion Ratio Calculator
Calculate your flock's feed conversion ratio (FCR) to evaluate how efficiently your lambs turn feed into weight gain.
How this calculator works
FCR measures efficiency. It tells you exactly how many units of feed were required to produce one unit of animal weight gain.
Formula used
FCR = Feed Consumed ÷ Total Weight Gain
Example calculation
If a lamb eats 60 lbs of feed and gains 12 lbs, the FCR is 60 ÷ 12 = 5.0. It took 5 lbs of feed to make 1 lb of lamb.
What to do with this result
Monitor FCR across different groups to identify the most efficient genetics and the most cost-effective rations.
Ready to track this for the whole flock?
One-off calculations are great for quick checks, but farm decisions are better when records are connected. HerdDeck Shepherd connects sheep records, weights, treatments, and feed costs in one easy app.
Try the DemoFrequently Asked Questions
A lower number is better. For lambs on a high-concentrate diet, an FCR of 4.0 to 5.5 is typical.
A high FCR means poor efficiency. This can be due to feed wastage, poor genetics, cold weather, or illness/parasites.
Yes. Young lambs are very efficient (low FCR). As they get heavier and start depositing fat, their FCR increases (becomes less efficient).
You must track exactly how much feed is delivered to the pen and subtract any feed that is wasted or refused.