Feed Conversion Ratio (FCR) Calculator
Enter the feed consumed and weight gained to get the FCR instantly. Switch to the full mode to calculate economic FCR (dressed weight), technical FCR (mortality-adjusted), and feed cost per kilogram of gain. Species benchmarks show how your flock or herd compares to industry targets.
Formula
Worked example
A broiler house uses 3,000 kg of feed over a 42-day cycle. Birds started at 0.04 kg each and ended at 2.5 kg (500 birds placed, 10 died). Gross weight gain = 490 survivors x 2.5 kg = 1,225 kg. Basic FCR = 3,000 / 1,225 = 2.45. With a 75% dressing percentage, economic FCR = 3,000 / (1,225 x 0.75) = 3.27. At 0.45 per kg feed, total feed cost = 1,350 and cost per kg live gain = 1.10.
What is feed conversion ratio (FCR)?
Feed conversion ratio (FCR) is the single most-used metric in livestock and aquaculture production. It expresses how many kilograms (or pounds) of feed an animal needs to produce one kilogram of live-weight gain or one kilogram of product. A broiler that eats 2 kg of feed for every 1 kg it gains has an FCR of 2.0. A beef steer requiring 8 kg of feed per kg of gain has an FCR of 8.0. Lower is always better because feed is typically the largest cost in any production system, often 60 to 80 percent of total variable costs.
Basic FCR vs economic FCR vs technical FCR
Basic FCR divides total feed by total live-weight gain and is the standard comparison metric. Economic FCR (also called dressed-weight FCR) divides feed by dressed or carcass weight, which accounts for the yield lost in slaughter and processing. Because a broiler with a 75% dressing yield loses a quarter of its live weight, economic FCR is roughly 1/0.75 (about 33%) higher than basic FCR for the same batch. Technical FCR adjusts for mortalities: it divides feed by the weight gain that only surviving animals could have contributed. Technical FCR is always at least as high as basic FCR and rises sharply when mortality is significant, making it the most honest single-figure measure of production system efficiency.
How to improve FCR on your farm
Four levers drive most FCR improvements. First, feed quality: a feed with the right amino-acid profile and digestible energy eliminates nutrient waste; cheap, poorly specified rations often cost more in feed per kg of gain than a more expensive well-balanced diet. Second, feed management: nipple drinkers positioned correctly, feeders adjusted to reduce spillage, and fresh feed daily reduce waste directly. Third, health: disease, gut damage, and parasite load all reduce nutrient absorption and push FCR up; vaccination, biosecurity, and prompt treatment have measurable effects. Fourth, genetics: modern broiler, pig, and salmon strains have been selectively bred for FCR over decades, so choosing the right breed or strain for your system and climate is foundational. Water quality matters enormously in aquaculture; dissolved oxygen, ammonia, and temperature all affect appetite and digestion in fish.
FCR, sustainability, and protein efficiency
FCR has become an important sustainability metric because it is closely correlated with land use, water use, and greenhouse gas emissions per kilogram of food produced. Monogastric animals (poultry, pigs, fish) convert feed to edible protein far more efficiently than ruminants (cattle, sheep). Salmon and tilapia reach FCRs below 1.5 in well-managed intensive systems because fish are cold-blooded and do not spend energy maintaining body temperature. Broilers have improved from an FCR of around 3.0 in the 1950s to 1.5 to 1.7 in modern commercial production through genetic selection and nutrition science. Reducing FCR by even 0.1 units across an entire production cycle meaningfully reduces feed use, cost, and environmental footprint.
FCR benchmarks by species
| Species | FCR range | Notes |
|---|---|---|
| Broiler chicken | 1.5 - 2 | Commercial indoor production |
| Layer chicken (eggs) | 2 - 2.5 | Per kg of eggs produced |
| Pig / swine | 2.7 - 3.9 | Grower-finisher phase |
| Salmon | 1.1 - 1.4 | Aquaculture; best-practice farms |
| Tilapia | 1.6 - 1.8 | Intensive pond or RAS systems |
| Catfish | 1.5 - 3 | Varies by system and feed quality |
| Sheep / lamb | 4 - 6 | Quality feed; can reach 8+ on forage |
| Beef cattle | 6 - 12 | Feedlot; ruminant digestion is less efficient |
| Rabbit | 2.5 - 4 | Grain diet; higher on forage |
Industry FCR targets under good management. Lower is better. Values are for live-weight gain (basic FCR) unless noted.
Frequently asked questions
What is a good FCR?
It depends entirely on the species. For broiler chickens an FCR below 1.8 is excellent; for salmon, below 1.3 is best-practice; for beef cattle, below 7.0 is very good. The reference table on this page lists typical ranges for the most common species. Within a species, any batch that beats the lower end of the range is performing well.
Why is a lower FCR better?
Because FCR measures how much feed you need per unit of product. Feed is the biggest cost in almost every livestock system. An FCR of 1.8 instead of 2.0 on a 500-bird broiler batch weighing 2.5 kg each at sale means roughly 250 fewer kg of feed purchased, which is a direct saving. Lower FCR also means less manure, lower ammonia output, and a smaller environmental footprint.
What is the difference between FCR and feed efficiency?
Feed efficiency is the reciprocal of FCR: it is weight gain divided by feed consumed. An FCR of 2.0 corresponds to a feed efficiency of 0.50 (50%). Some livestock sectors, particularly the beef and sheep industries, historically used feed efficiency instead of FCR. Both express the same relationship; FCR is now the more common global standard.
How does mortality affect FCR?
Mortalities increase the true FCR of a batch because the feed those animals consumed produced no saleable weight. Technical FCR captures this by dividing all feed consumed by the weight gain attributable only to survivors. If 2% of animals die mid-cycle having eaten feed but not contributed to final weight, technical FCR will be higher than basic FCR. High-mortality batches can look acceptable on basic FCR but very poor on technical FCR.
Can FCR be below 1.0?
In live-weight terms, an FCR below 1.0 is theoretically impossible for land animals (you cannot produce more mass than you feed) but is occasionally reported for fish. The reason is moisture: fish can absorb water from their aquatic environment, so their body mass gain can occasionally exceed dry-matter feed intake when the feed is measured on a dry basis. In practice, FCR below 1.0 for fish usually signals a measurement error.
How is FCR different for egg-laying hens?
For layer hens, FCR is calculated as feed consumed divided by total egg mass produced (not live-weight gain of the bird). A common target is 2.0 to 2.5 kg of feed per kg of eggs. This figure is not directly comparable to meat-animal FCR because the product (eggs) has a different water and protein content from muscle tissue.