toolbox
Home / Farming, Animals & Pets / Pig Feed Feed Conversion Calculator

Pig Feed Feed Conversion Calculator

Calculate pig feed conversion ratio (FCR) from the total feed consumed and the live-weight gain produced over the same period. FCR expresses how many units of feed were used for each unit of weight gain, so lower values indicate less feed used per unit of gain when the figures are measured consistently.

The calculator also shows feed per pig and gain per pig to make group records easier to interpret. It is suitable for comparing batches, production periods, or feeding programs when the feed and gain data cover the same animals and dates. FCR alone does not explain why performance changed; genetics, health, mortality, feed composition, starting weight, environment, and measurement methods can all affect the ratio.

Pig feed conversion inputs

kg
kg
pigs
days
Result
—
feed conversion ratio (feed ÷ gain)
Feed per pig—
Gain per pig—
Feed per pig per day—

1. Enter total feed consumed
Use feed actually consumed by the group during the measurement period, not feed delivered if known refusals or losses are excluded from your records.

2. Enter total live-weight gain
Use the combined ending-minus-starting live-weight gain for the same group and period.

3. Add pig count and days
These values do not change FCR, but they produce useful per-pig context in the result breakdown.

4. Check that records align
Feed and gain must cover the same pigs and the same dates for a meaningful ratio.

5. Interpret the FCR
The main result is kilograms of feed per kilogram of live-weight gain when both inputs are in kilograms.

Feed conversion ratio = Total feed consumed ÷ Total live-weight gainFeed per pig = Total feed consumed ÷ Number of pigsGain per pig = Total live-weight gain ÷ Number of pigs

Where:

  • Total feed consumed = feed consumed over the period in kg
  • Total live-weight gain = combined live-weight gain over the same period in kg
  • Number of pigs = animals represented by the group data
  • Period length = days represented by the records

Assumptions: Feed and weight gain must be measured on consistent group boundaries. Weight gain must be greater than zero.

What the result means

The FCR shows how many kilograms of feed were consumed for each kilogram of live-weight gain over the recorded period.

Use consistent definitions for feed use, mortality adjustments, and group weights when comparing FCR between batches.

Given

  • Total feed consumed: 9,240 kg
  • Total live-weight gain: 3,360 kg
  • 96 pigs
  • Period: 42 days

Calculation
FCR = 9,240 ÷ 3,360 = 2.75.
Feed per pig = 9,240 ÷ 96 = 96.25 kg.
Gain per pig = 3,360 ÷ 96 = 35.00 kg.

Result
2.750

Interpretation
The group used 2.75 kg of feed for each kilogram of live-weight gain during the measured 42-day period.

Is a lower FCR always better?

A lower FCR means less recorded feed per unit of recorded gain, but comparisons are only fair when pig type, weight range, health, mortality treatment, and measurement method are comparable.

Should feed wastage be included?

Use the definition that matches your management objective and apply it consistently. If you want biological feed efficiency, consumed feed is more appropriate; if you want purchased-feed efficiency, losses may need to remain in the feed figure.

What if the group lost weight?

FCR based on positive gain is not meaningful when total live-weight gain is zero or negative. The calculator requires gain greater than zero.

Why enter pig count if it does not change FCR?

Pig count allows the page to show feed and gain per pig. Those supporting figures can reveal whether two groups with similar FCR had very different scale or individual performance.

How is FCR different from average daily gain?

FCR relates feed input to weight gain. Average daily gain relates weight gain to time, so the two metrics describe different parts of growth performance and are often reviewed together.