Feed Conversion Ratio Calculator
Turn pen weights and feed delivered into feed conversion on a dry matter and as-fed basis, plus feed cost per pound of gain.
Your numbers
18.0 lb DM intake ÷ 3.00 lb/day ADG
6.00 : 1 dry matter feed conversion
- As-fed feed conversion
- 8.00 : 1
- Feed cost per lb of gain
- $0.780
- Total pen feed used (as fed)
- 288,000 lb
- On a dry matter basis this pen is converting at 6.00:1 — compare it to the class averages in the reference table below.
- At 75% dry matter the as-fed and dry matter conversions are reasonably close.
- Feed refusals, bunk sorting and waterer losses all inflate measured intake without adding gain, so actual pen conversion is often somewhat worse than a controlled research trial.
Show the math
- Total gain and ADG960 − 600 = 360 lb ÷ 120 days = 3.00 lb/day
- Dry matter intake24.0 lb as fed × 75% = 18.0 lb DM/day
- Dry matter feed conversion18.0 lb DM ÷ 3.00 lb gain = 6.00 : 1
- As-fed feed conversion24.0 lb as fed ÷ 3.00 lb gain = 8.00 : 1
- Feed cost per pound of gain(24.0 lb ÷ 2,000 × $195/ton) ÷ 3.00 lb gain = $0.780
- Total pen feed used24.0 lb/day × 120 days × 100 head = 288,000 lb
Assumptions this calculator used
Nothing here is hidden. Change any figure you have better local data for.
How to calculate feed conversion ratio
Feed conversion ratio is a physical efficiency measure, not a dollar measure: pounds of feed consumed per pound of gain produced. Because rations vary widely in moisture, the fair comparison across pens or across time is always on a dry matter basis — as-fed numbers only tell you about the specific ration you fed.
ADG = (ending weight − starting weight) ÷ days on feed
DM intake = as-fed intake × ration dry matter %
FCR (dry matter) = DM intake ÷ ADG
FCR (as fed) = as-fed intake ÷ ADG
Feed cost/lb gain = (as-fed intake ÷ 2,000 × $/ton as fed) ÷ ADG
Worked example
A pen of 100 steers goes from 600 lb to 960 lb over 120 days, a gain of 360 lb per head and 3.0 lb/day ADG. They eat 24 lb of as-fed ration per head per day at 75% dry matter, or 18 lb of dry matter. Dry matter conversion is 18 ÷ 3.0, or 6.0:1; as-fed conversion is 24 ÷ 3.0, or 8.0:1. At $195 a ton as fed, feed cost per pound of gain is roughly $0.78.
Common mistakes
- Comparing as-fed conversions across different rations. A wet, silage-heavy ration will always show a worse as-fed number than a dry ration even at identical true efficiency — compare on dry matter.
- Using book intake instead of actual bunk deliveries. Feed conversion is only as accurate as the intake and weight records feeding the calculation.
- Ignoring feed waste and refusals. Feed pushed out of the bunk, dropped from a wagon, or spoiled counts as intake on paper but adds nothing to gain.
- Expecting the same conversion at every weight. Conversion worsens as cattle approach finished weight because a larger share of intake goes to maintenance rather than growth.
Typical dry-matter feed conversion by class of cattle
Approximate feed conversion ranges and ADG by class, on a dry matter basis. Actual performance depends on ration energy density, health, genetics, and season.
| Class | Dry matter FCR | Typical ADG |
|---|---|---|
| Calf-fed steers (550-950 lb) | 5.5 - 6.5 : 1 | 2.8 - 3.4 lb/day |
| Calf-fed heifers (500-850 lb) | 6.0 - 7.0 : 1 | 2.4 - 3.0 lb/day |
| Yearling steers (750-1,250 lb) | 6.0 - 7.0 : 1 | 3.0 - 3.8 lb/day |
| Yearling heifers (700-1,100 lb) | 6.5 - 7.5 : 1 | 2.6 - 3.2 lb/day |
| Backgrounding, growing ration | 7.0 - 9.0 : 1 | 1.8 - 2.6 lb/day |
| Grow ration to 800 lb | 6.5 - 8.0 : 1 | 2.2 - 2.8 lb/day |
| High-concentrate finishing | 5.8 - 7.0 : 1 | 3.0 - 4.0 lb/day |
| Late finishing (near slaughter weight) | 7.5 - 9.0 : 1 | 2.5 - 3.2 lb/day |
| Dairy-beef crossbred steers | 6.0 - 7.5 : 1 | 2.8 - 3.6 lb/day |
Calculators to run next
- Creep Feed CalculatorUse before rolling a creep feeder out to the calves this summer.
- Cattle Mineral Intake CalculatorUse when consumption is running over or under label target and mineral costs are drifting.
- Silage Tonnage CalculatorUse to inventory a bunker before winter or to size a pile at harvest.
- Bunk Space CalculatorUse when timid cattle are falling behind or you are laying out a new pen.
- Dry Matter Intake CalculatorStart here — intake sets the size of every ration and feed budget that follows.
- Cattle Protein Supplement CalculatorUse when the hay tests short on protein and you need a feeding rate and a cost.
Questions ranchers ask
How do you calculate feed conversion ratio in cattle?
Divide the pounds of feed consumed by the pounds of gain produced over the same period. If a pen ate 20 lb of dry matter per head per day and gained 3 lb per head per day, the dry matter feed conversion is 20 ÷ 3, or 6.67 to 1.
What is a good feed conversion ratio for feeder cattle?
On a dry matter basis, calf-fed steers commonly run 5.5 to 6.5:1, yearlings 6.0 to 7.0:1, and heavier cattle finishing near slaughter weight can run 8:1 or higher because maintenance requirements take a larger share of intake as cattle get bigger.
What is the difference between dry matter and as-fed feed conversion?
As-fed conversion uses the actual pounds of ration delivered to the bunk, water and all. Dry matter conversion strips the water out first. A wet, high-moisture ration will always show a worse as-fed conversion than the same ration's dry matter conversion, so DM basis is the fair way to compare rations of different moisture.
Why does feed conversion get worse as cattle get heavier?
Maintenance energy requirement rises with body weight, and a growing share of daily intake goes to maintaining existing tissue rather than building new tissue. A 1,300 lb steer needs more total feed to maintain itself than an 700 lb steer, so each pound of gain costs more feed even on an identical ration.
How is feed conversion different from cost of gain?
Feed conversion is a physical efficiency measure — pounds of feed per pound of gain — with no dollars in it. Cost of gain takes that physical efficiency and multiplies it by your feed price, plus adds yardage, health and financing costs that feed conversion ignores entirely.
Does breed or sex affect feed conversion ratio?
Yes. Steers typically convert somewhat better than heifers at the same stage, and continental or larger-framed cattle often show slightly better conversion at moderate weights than smaller-framed British breeds because of differences in maintenance requirement and growth rate.
How much dry matter should I use if I only know the ration's as-fed weight?
Multiply as-fed pounds fed by the ration's dry matter percentage from a feed test or your mixer sheet. A high-moisture corn or silage-based ration commonly runs 55 to 75% dry matter, while a dry, complete pelleted or hay-based ration can run 85 to 92%.
Why does my calculated feed conversion look worse than what a feedlot reports?
Reported feedlot FCR figures are usually pen averages under ideal bunk management with minimal feed waste and tight sorting by weight. Feed refusals, bunk sorting, waterer leaks and health pulls all inflate real-world intake without adding gain, which worsens the true conversion on a smaller or less controlled operation.
Efficient cattle start with a solid purchase
Feed conversion is shaped as much by the cattle you start with as by the ration you feed them. Agrilot's verified auction listings include weights, health history and seller records so you can judge a set's likely performance before you commit a pen to it.