Last updated: June 19, 2026
Feed Conversion Ratio Calculator
Creators
Dharmendra SinghReviewers
Creators
Dharmendra SinghReviewers
Quick Answer
The Feed Conversion Ratio Calculator computes FCR = total feed consumed ÷ weight gained (end weight − start weight), where a lower number means more efficient conversion of feed into body weight. It also reports feed efficiency, the inverse expressed as a percentage (gain ÷ feed × 100). Typical FCR ranges vary by species: farmed fish 1.0–1.8, broiler chickens 1.5–2.0, pigs 2.5–3.5, rabbits 3.0–4.0, sheep 4.0–6.0, and beef cattle 6.0–10.0, because monogastric animals convert feed far more efficiently than ruminants. For example, a pig eating 272 kg of feed to grow from 25 kg to 110 kg has an FCR of 272 ÷ 85 = 3.2. The calculator rates the result against the typical range for the chosen species. Feed is 60–70% of production cost, so improving FCR is the main lever for profitability and sustainability.
Feed conversion ratio is the feed eaten divided by the weight gained, and a lower number is better. For example, a pig that eats 272 kilograms of feed to gain 85 kilograms has a feed conversion ratio of 3.2. Typical values are about 1.5 to 2 for broiler chickens and 6 to 10 for beef cattle.
Key Takeaways
- FCR = total feed consumed ÷ weight gained — a lower number is more efficient
- Feed efficiency is the inverse: gain ÷ feed × 100 (higher is better)
- Typical FCR: fish 1.0–1.8, broilers 1.5–2.0, pigs 2.5–3.5, cattle 6–10
- Monogastric animals (poultry, pigs, fish) convert feed far better than ruminants
- FCR worsens as animals age and approach market weight
- Feed is 60–70% of production cost, so small FCR gains have big economic impact
Creators
Dharmendra SinghReviewers
Creators
Dharmendra SinghReviewers
Formula
FCR = Feed Consumed ÷ (End Weight − Start Weight)
Where:
- FCR=Feed conversion ratio (lower is better)
- F=Total feed consumed(kg)
- W_{end} - W_{start}=Weight gained over the period(kg)
Worked Examples
Broiler chicken flock
A broiler raised from a 50 g chick to 2.05 kg, eating 2.9 kg of feed.
- 1Weight gained = 2.05 − 0.05 = 2.0 kg
- 2FCR = 2.9 ÷ 2.0 = 1.45
- 3Feed efficiency = 2.0 ÷ 2.9 × 100 = 68.97%
- 4Typical broiler FCR is 1.5–2.0
- 51.45 is below the range → Excellent efficiency
Grower-finisher pig
A pig grown from 25 kg to 110 kg, eating 272 kg of feed.
- 1Weight gained = 110 − 25 = 85 kg
- 2FCR = 272 ÷ 85 = 3.2
- 3Feed efficiency = 85 ÷ 272 × 100 = 31.25%
- 4Typical swine FCR is 2.5–3.5
- 53.2 is within the range → Good
Farmed tilapia
A tilapia grown from 50 g to 600 g, fed 0.85 kg of pellets.
- 1Weight gained = 0.60 − 0.05 = 0.55 kg
- 2FCR = 0.85 ÷ 0.55 = 1.55
- 3Feed efficiency = 0.55 ÷ 0.85 × 100 = 64.71%
- 4Typical farmed-fish FCR is 1.0–1.8
- 51.55 is within the range → Good (fish are very efficient)
Feedlot beef steer
A steer grown from 250 kg to 600 kg, eating 2,800 kg of feed.
- 1Weight gained = 600 − 250 = 350 kg
- 2FCR = 2800 ÷ 350 = 8.0
- 3Feed efficiency = 350 ÷ 2800 × 100 = 12.5%
- 4Typical beef FCR is 6.0–10.0
- 58.0 is within the range → Good (ruminants are less efficient than poultry)
Introduction
The Feed Conversion Ratio Calculator works out how efficiently an animal turns feed into body weight — the single most important number in profitable, sustainable animal production. FCR = feed consumed ÷ weight gained. A broiler chicken with an FCR of 1.6 eats 1.6 kg of feed for every 1 kg of weight it puts on; a beef steer might need 6–10 kg. A lower FCR means less feed (and lower cost and environmental footprint) per kilogram produced. This tool also reports feed efficiency (the inverse, as a percentage) and rates your result against typical industry ranges for poultry, pigs, fish, sheep, rabbits and cattle. For related tools see our Dry Matter Calculator, Cattle Per Acre Calculator, and Dog Food Calculator.
What Is Feed Conversion Ratio?
Feed conversion ratio (FCR) is the mass of feed an animal eats divided by the live weight it gains over the same period. It's a pure ratio, so it has no units (kg feed per kg gain).
- **Formula:
** FCR = total feed consumed ÷ weight gained
- **Lower is better:
** a smaller FCR means more growth from less feed
- **Feed efficiency** is the inverse:
weight gained ÷ feed, often shown as a %
Always use the same units for feed and weight (e.g. both in kg)
Can be measured per animal or for a whole group — the ratio is the same
Feed is usually 60–70% of the total cost of raising an animal, so even a 0.1 improvement in FCR can transform the profitability of a farm.
How to Calculate FCR
You need just two numbers: how much feed was eaten, and how much weight was gained over the same window.
- **Step 1:
** Record total feed consumed over the period (kg)
- **Step 2:
** Weigh the animal(s) at the start and end; weight gained = end − start
- **Step 3:
** Divide: FCR = feed ÷ weight gained
- Example:
272 kg feed ÷ 85 kg gain = FCR 3.2 (a typical grower pig)
- For feed efficiency, flip it:
85 ÷ 272 × 100 = 31% efficiency
Typical FCR by Species
FCR varies enormously between species because of differences in metabolism, digestion and how much energy goes into maintenance versus growth. Monogastric animals (poultry, pigs, fish) are far more efficient than ruminants (cattle, sheep).
| Species | Typical FCR | Why |
|---|---|---|
| Farmed fish (tilapia, salmon) | 1.0–1.8 | Cold-blooded — little energy spent on body heat |
| Broiler chicken | 1.5–2.0 | Fast-growing, highly selected for efficiency |
| Pig / swine | 2.5–3.5 | Efficient monogastric, larger maintenance cost |
| Rabbit | 3.0–4.0 | Small herbivore, moderate efficiency |
| Sheep / lamb | 4.0–6.0 | Ruminant — fermentation has an energy cost |
| Beef cattle | 6.0–10.0 | Large ruminant, high maintenance energy |
Values are typical good-practice ranges for growing animals. Young animals convert feed more efficiently than older ones, so FCR rises as an animal approaches market weight.
FCR vs Feed Efficiency
FCR and feed efficiency describe the same thing from opposite directions — it helps to know both.
| Metric | Formula | Direction | Example (pig) |
|---|---|---|---|
| Feed conversion ratio (FCR) | feed ÷ gain | Lower is better | 272 ÷ 85 = 3.2 |
| Feed efficiency (FE) | gain ÷ feed × 100 | Higher is better | 85 ÷ 272 = 31% |
| Relationship | FE = 100 ÷ FCR | Inverse | 100 ÷ 3.2 ≈ 31% |
Poultry and fish industries usually quote FCR; some swine and dairy systems prefer feed efficiency or 'gain-to-feed'. They're interchangeable.
What Affects Feed Conversion Ratio
Many management and biological factors push FCR up or down. Improving FCR is mostly about reducing wasted or maintenance feed.
- **Genetics:
** modern broiler and pig lines are bred for low FCR
- **Diet quality:
** balanced energy and protein (and digestibility) lower FCR
- **Age/weight:
** younger animals convert feed more efficiently than older ones
- **Health:
** parasites, disease and stress all worsen FCR
- **Temperature:
** animals outside their comfort zone burn feed on heating/cooling
- **Feed wastage:
** spillage and spoilage inflate measured FCR — feeder design matters
- **Water quality:
** poor water intake reduces feed intake and gain
Because FCR includes feed that's wasted, two farms with identical animals can show very different FCRs purely from feeder design and spillage.
Why FCR Matters — Cost and Sustainability
FCR is both an economic and an environmental lever.
- **Cost:
** feed is the biggest single expense in animal production; lower FCR = lower cost per kg
- **Profit:
** a flock with FCR 1.6 vs 1.8 can mean a large margin difference at scale
- **Environment:
** less feed per kg means less land, water and greenhouse gas per kg of meat
- **Benchmarking:
** tracking FCR over batches reveals health or management problems early
- **Feed planning:
** combine with our Dry Matter Calculator to compare feeds on a fair basis
Glossary
Quick definitions for the terms used in this calculator:
| Term | Definition |
|---|---|
| FCR | Feed conversion ratio — feed eaten per unit of weight gained (lower is better). |
| Feed efficiency | Weight gained per unit of feed, the inverse of FCR (higher is better). |
| Weight gain | Live weight at the end minus live weight at the start of the period. |
| Monogastric | Single-stomached animals (poultry, pigs, fish) — generally efficient converters. |
| Ruminant | Animals that ferment feed in a rumen (cattle, sheep) — higher FCR. |
| Maintenance feed | Feed used just to keep an animal alive, before any growth. |
| As-fed / DM basis | Whether feed is measured as eaten or after removing water — keep it consistent. |
Quick Reference Card
Feed Conversion Ratio — Quick Reference
Quick reference • Feed Conversion Ratio Calculator
FCR = feed consumed ÷ weight gained · Feed efficiency = gain ÷ feed × 100 = 100 ÷ FCRValid range: Lower is better · fish 1.0–1.8 · broiler 1.5–2.0 · pig 2.5–3.5 · cattle 6–10
Common Values
⚠ Watch Out
- •Keep feed and weight in the same units (e.g. both kg)
- •Don't mix as-fed and dry-matter feed weights
- •Lower FCR is better — don't confuse it with feed efficiency
- •FCR rises as animals get older and heavier
Pro Tips
- →Track FCR per batch to catch health or feed problems early
- →Cut feed wastage — spillage inflates your measured FCR
- →Market animals at target weight before efficiency declines
- →Compare feeds fairly with our Dry Matter Calculator first
FAQs
What is a good feed conversion ratio?
It depends entirely on the species. For farmed fish a good FCR is around 1.0–1.5, for broiler chickens about 1.5–1.8, for pigs roughly 2.5–3.0, and for beef cattle 6–8. A 'good' FCR is one at or below the typical range for that animal — and remember, lower is always better because it means less feed per kilogram of gain. This calculator rates your result against the typical range for the species you choose.
Is a higher or lower FCR better?
Lower is better. FCR is the amount of feed needed to produce one kilogram of weight gain, so a lower number means the animal is converting feed into growth more efficiently and you're spending less on feed. For example, an FCR of 1.5 is more efficient than 2.0. If you prefer 'higher is better', use feed efficiency (gain ÷ feed), which is simply the inverse of FCR.
How do I calculate feed conversion ratio?
Divide the total feed consumed by the weight gained over the same period: FCR = feed ÷ (end weight − start weight). For instance, a pig that ate 272 kg of feed while growing from 25 kg to 110 kg gained 85 kg, giving an FCR of 272 ÷ 85 = 3.2. Just make sure the feed and weights are in the same units (usually kilograms).
Why do cattle have a much higher FCR than chickens?
Because of body size and digestion. Cattle are large ruminants that spend a lot of energy on maintenance and on fermenting fibrous feed in the rumen, which is less efficient for growth than the simple digestion of a chicken or fish. Chickens are also small, fast-growing and heavily selected for feed efficiency. That's why broilers sit around 1.5–2.0 while beef cattle are 6–10 — both are normal for their species.
Should I use as-fed or dry-matter weight for feed?
Either is fine as long as you're consistent and compare like with like. Most commercial FCR figures use as-fed feed weight. If you want to compare feeds with very different moisture (e.g. silage vs pellets), convert both to a dry-matter basis first using our Dry Matter Calculator, then compute a dry-matter FCR. Mixing as-fed and dry-matter values will give a misleading ratio.
Does FCR change as an animal grows?
Yes — FCR generally gets worse (higher) as an animal gets bigger. Young animals put most of their feed energy into growth, while older, heavier animals spend more on maintenance, so each extra kilogram of gain costs more feed. This is why producers often have a target market weight: pushing animals well beyond it makes the FCR (and cost per kg) climb steeply.
How can I improve my animals' feed conversion ratio?
Focus on the factors that waste feed or energy: feed a well-balanced, digestible diet; keep animals healthy and parasite-free; maintain a comfortable temperature; provide clean water; minimise feed spillage with good feeder design; and market animals at the right weight before efficiency declines. Genetics matter too — modern, well-selected breeds convert feed far more efficiently than older lines.