Calculate your flock’s FCR
FCR 1.72, 0.33 above the Ross 308 target for day 35.
- Livability
- 98.0%
- EPEF
- 308
- Feed per bird
- 3,200 g
Against the breed target Ross 308 · day 35
Ross 308 target FCR at day 35: 1.399
- Target weight
- 2,296 g
- Your FCR vs target
- +0.33
- Your weight vs target
- −396 g
- Feed above target
- 5,926 kg
- Cost of that feed
- Add a feed price
Feed above target = your feed − target FCR × your weight gain.
JavaScript is off, so the live calculator is not running. The worked example below shows every step, so you can do the same sum by hand.
The FCR formula
FCR is the feed conversion ratio: how many kilograms of feed it took to grow one kilogram of live bird.
A lower FCR is better, because the flock turned less feed into more weight. A 2025 study of large broiler farms in Punjab found FCRs from about 1.45 to 1.7.
FCR = feed (kg) ÷ weight gain (kg)
Weight gain = birds alive × average live weight + the live weight of the birds already sold − birds placed × chick weight at placement. Dead birds are left out. Poultry Ledger takes each sale’s weight from the kanta weight recorded with it or, if it was not weighed, from the latest sample before the sale. This calculator has no field for birds sold, so it is right for a flock that has not been sold yet.
Roman Urdu
FCR = feed (kg) ÷ wazan gain (kg).
Misaal: 31,360 kg feed ÷ 18,180 kg gain = 1.72. Kam FCR behtar hai.
The four figures
- FCR
- feed ÷ weight gain Feed in kg to grow one kg of bird. Lower is better. It is gain-based, so the chick weight is taken out first.
- Livability
- 100 − deaths ÷ placed × 100 The share of placed chicks that did not die. Birds already sold still count. 98% livability means 2% died.
- EPEF
- liv × kg ÷ (age × FCR) × 100 The European Production Efficiency Factor rolls weight, age, FCR and livability into one score. Higher is better; good flocks often score around 350 to 400.
- Feed per bird
- feed ÷ (placed − deaths) Total feed divided by the birds that did not die: the birds in the shed plus any already sold. Useful when you order the next load of feed.
How to measure feed and weight
The answer is only as good as the two numbers that go in. Take a few minutes over them.
Feed used (kg)
- Count every bag delivered to this shed since the chicks were placed.
- Take away the full bags still in the shed, and any bags moved to another shed.
- Multiply the bags used by the weight printed on the bag. That is your feed in kg.
- Include pre-starter and starter feed. They count too.
Average live weight (g)
- Weigh birds from the front, the middle and the back of the shed, not only the birds near the door.
- Weigh at the same time of day each time, so the birds’ crops are in the same state.
- Add up the weights and divide by the number of birds weighed. That is the average weight of one bird.
- Count the deaths up to the same day, so the birds-alive figure matches the weight.
Worked example: a 10,000-bird flock at day 35
A sample flock of Ross 308, one week before sale. It is not the example farm shown on the rest of the site. The calculator above opens with these same numbers.
| Input | Value |
|---|---|
| Total feed used | 31,360 kg |
| Birds placed | 10,000 |
| Total deaths | 200 |
| Birds alive | 9,800 |
| Average live weight | 1,900 g |
| Age today | 35 days |
| Breed | Ross 308 |
The working
- Live weight = 9,800 birds × 1.900 kg = 18,620 kg.
- Chick weight placed = 10,000 × 0.044 kg = 440 kg.
- Weight gain = 18,620 − 440 = 18,180 kg.
- FCR = 31,360 ÷ 18,180 = 1.725, shown as 1.72.
- Livability = 100 − (200 ÷ 10,000 × 100) = 98.0%.
- EPEF = 98.0 × 1.900 ÷ (35 × 1.725) × 100 = 308.
For this example: FCR 1.72 Ross 308 target FCR at day 35: 1.399
Ross 308 and Cobb 500 FCR by age
Breeder targets for live weight and cumulative FCR at the end of each week. Judge your flock against the target for its own age, not only at sale.
Real flocks usually finish a little above the breeder targets. A 2025 study of large broiler farms in Punjab reported a market age of 37 to 44 days and FCRs of about 1.45 to 1.7.
Field figures: Amin et al. 2025, Heliyon, “Comparative evaluation of management practices among large-scale broiler farms of Punjab, Pakistan”.
| Day | Ross 308 weight (g) | Ross 308 FCR | Cobb 500 weight (g) | Cobb 500 FCR |
|---|---|---|---|---|
| 7 | 213 | 0.780 | 202 | 0.891 |
| 14 | 533 | 1.005 | 570 | 1.029 |
| 21 | 1,012 | 1.142 | 1,116 | 1.182 |
| 28 | 1,616 | 1.269 | 1,783 | 1.322 |
| 35 | 2,296 | 1.399 | 2,521 | 1.441 |
| 42 | 2,998 | 1.531 | 3,278 | 1.555 |
| 49 | 3,681 | 1.663 | 4,001 | 1.686 |
| 56 | 4,318 | 1.793 | 4,641 | 1.842 |
These are breeder targets, not a promise. Real flocks change with weather, feed, health and care. Day-by-day tables: Ross 308 weight chart Cobb 500 weight chart
What a higher FCR costs
Every point of FCR is feed. Multiply the gap between your FCR and the target by the flock’s weight gain, and you have the extra feed in kg.
The table shows this for the sample flock, which put on 18,180 kg. To see it in rupees, enter your own feed price in the calculator. Prices change from mill to mill and week to week, so we do not guess one.
| FCR above target | Extra feed (kg) |
|---|---|
| 0.05 | 909 |
| 0.10 | 1,818 |
| 0.20 | 3,636 |
| This example: 31,360 − 1.399 × 18,180 | 5,926 |
Common FCR mistakes
-
Counting bags delivered, not bags used
Full bags still in the shed have not been eaten. Take them away first.
-
Using birds placed instead of birds alive
Birds that died ate feed but are not there to weigh. Use the birds alive now.
-
Mixing grams and kilograms
Feed goes in kilograms and the bird’s weight in grams. 1,900 g is 1.9 kg.
-
Comparing with the wrong age
FCR rises as birds get older. Compare a day-28 flock with the day-28 target.
-
Weighing only the easy birds
Birds near the door or the feeders are not the whole shed. Weigh from several places.
-
Comparing with a different formula
This calculator takes the chick weight out of the gain. A plain feed ÷ live weight figure reads a little lower.
How Poultry Ledger does this for you
In the app you never type these sums. You record feed, weights and deaths through the day, and Poultry Ledger keeps the running FCR, livability and EPEF for every flock.
- Feed is recorded as it is issued to each flock, and the stock goes down by itself.
- Deaths and sample weights are recorded by shed on Today’s Log, with one key each.
- FCR, EPEF and livability are worked out for every flock as the day is entered.
- A flock whose breed is set to Ross 308 or Cobb 500 is shown against that target for its age.
FCR questions
What is a good FCR for broilers?
Lower is better, and the right number depends on breed and age. The Ross 308 target at day 35 is 1.399 and the Cobb 500 target is 1.441. A 2025 study of large farms in Punjab found field FCRs of about 1.45 to 1.7.
Is this raw or corrected FCR?
This is raw, gain-based FCR: feed divided by live-weight gain. It is not corrected to a standard weight. Poultry Ledger uses the same gain-based method, and adds the weight of any birds already sold to the gain.
Why subtract the chick weight?
Because the chicks already weighed something when they were placed. Taking it out measures only the weight the feed added. It makes the FCR a little stricter and more honest.
Why does FCR go up as the flock gets older?
Heavier birds use more of each day’s feed just to keep their bodies going, so every extra kg of weight costs more feed. That is why the breed targets rise each week, and why you should compare at the same age.
What is EPEF and what is a good score?
EPEF puts livability, weight, age and FCR into one number: livability × weight (kg) ÷ (age × FCR) × 100. Higher is better. Good flocks often score around 350 to 400.
Does the calculator save my numbers?
No. Nothing is sent anywhere or saved. It works in your browser, even offline once the page has loaded.
FCR at a glance
- Ross 308 target, day 35
- 1.399
- Cobb 500 target, day 35
- 1.441
- Punjab farms, 2025 study
- 1.45–1.70
Lower is better. Compare your flock with the target for its age, not with one fixed number.
Send us your flock’s numbers
Message us on WhatsApp with the feed, birds, weight and age, and your question. We reply on WhatsApp.
0303-5655167Weight charts and the record-keeping guide
Let the app keep your FCR up to date.
Poultry Ledger works out FCR, livability and EPEF for every flock from the feed, weights and deaths you record, and shows each one against its Ross 308 or Cobb 500 target.
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