Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Value lost to shrink
$24,750
Tons lost
450.0
Usable tons remaining
2,550.0
Shrink rate applied
15.0%
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How to use this
- 1Enter tons ensiled (as-fed).
- 2Enter storage type.
- 3Enter override shrink % (0 = use storage default) (%).
- 4Enter value per ton as-fed ($).
- 5Read your value lost to shrink on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Shrink is the silent cost of silage feeding: dry matter that disappears between the chopper and the feed bunk through fermentation gas loss, seepage, and surface spoilage. Bunker and pile silos routinely lose 12-20% of tonnage, while well-managed ag bags and tower silos can hold shrink to 5-8%. This calculator takes the tons ensiled, applies a shrink percentage based on storage type and management, and converts the loss into feed value dollars using your as-fed cost of production or purchase equivalent. It's the number that explains why two farms with identical yields end up with very different feed bills, and it's the lever most within reach through better packing density, faster fill, and tighter covering.
Worked example
Using the values the calculator loads with:
Inputs
- Tons ensiled (as-fed): 3000
- Storage type: Bunker/drive-over pile (15% shrink)
- Override shrink % (0 = use storage default): 0 %
- Value per ton as-fed: 55 $
Results
- Value lost to shrink: $24,750
- Tons lost: 450
- Usable tons remaining: 2,550
- Shrink rate applied: 15.0%
What each field means
Inputs
- Tons ensiled (as-fed)
- The tons ensiled (as-fed) used in the calculation. Starts at 3000 so you have a working example on load.
- Storage type
- Pick the option that matches your situation — the maths changes per option. Choices: Bunker/drive-over pile (15% shrink), Ag bag (8% shrink), Tower silo (7% shrink), Wrapped baleage (10% shrink).
- Override shrink % (0 = use storage default) (%)
- The override shrink % (0 = use storage default) used in the calculation, measured in %. Starts at 0 % so you have a working example on load. Accepted range: 0–40 %.
- Value per ton as-fed ($)
- The value per ton as-fed used in the calculation, measured in $. Starts at 55 $ so you have a working example on load.
Results
- Value lost to shrink
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Tons lost
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Usable tons remaining
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Shrink rate applied
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
What cuts bunker silo shrink the most?
Packing density is the biggest lever — targeting 44+ lb of dry matter per cubic foot versus a loose 30-35 lb can cut shrink by a third. Fast fill (under 3 days), immediate tight covering with oxygen-barrier film, and quick feedout rate (removing 6+ inches per day) round out the rest.
Why is baleage shrink higher than tower silos?
Individually wrapped bales have far more surface area exposed to potential film damage per ton stored, and any tear or puncture lets in oxygen that spoils that whole bale. Tower silos have minimal surface-to-volume ratio, which is why they shrink least despite being less common now.
Is shrink the same as feed-out waste at the bunk?
No, this calculator only covers storage shrink from fermentation and spoilage before feeding. Bunk refusal and push-up losses are a separate, additional loss that typically runs another 2-5% on top of storage shrink.
How do I actually measure my shrink?
Weigh or estimate tons going in at harvest using yield monitor data or load counts, then track tons fed out using TMR mixer loads. The gap between the two, adjusted for any beginning/ending inventory, is your real shrink number.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Hay Bale Cost Per Ton Calculator
Compare round and square bale pricing on an apples-to-apples ton basis.
Dairy Feed Cost Per Cwt Calculator
Daily ration cost translated into feed cost per hundredweight of milk shipped.
Corn Silage Yield Estimator
Estimate tons of silage per acre from expected grain yield.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Silage Shrink Loss Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/silage-shrink-loss
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/silage-shrink-loss" target="_blank" rel="noopener">Silage Shrink Loss Calculator — RevenueLab</a> (2026).</p>
Source: [Silage Shrink Loss Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/silage-shrink-loss) (2026).