Grain Bin Calculator
Use this grain bin calculator to estimate storage volume and grain capacity from bin dimensions. The page follows the Omni grain-bin idea of converting cubic feet into bushels using the standard factor of 0.7786 bushels per cubic foot, and it also converts that capacity into cubic meters and estimated grain weight from a test weight input.
--
Run the calculator.
What This Grain Bin Calculator Helps You Do
This page brings the calculator, formula, examples, and reference notes into one V3 layout so the workflow is easier to follow and easier to verify. Instead of leaving the logic separated from the explanation, the page keeps the main inputs and the educational content together.
Use the calculator first to get a quick answer, then use the formula and examples sections to understand how the result is derived. That pattern is useful when you need a fast answer now but still want enough detail to check that the output matches the task you are solving.
The related FAQ and reference sections also help reduce misinterpretation. They are meant to explain where the formula applies, where assumptions matter, and when a simple calculator result should be treated as a planning estimate rather than a final professional conclusion.
How to Calculate Grain Bin Calculator
- Choose the bin shape: Select round or rectangular and enter the matching footprint dimensions.
- Enter wall height: Use the height of the straight storage section.
- Add roof and hopper sections if needed: These sections are treated as one-third-height geometric sections for planning.
- Convert cubic feet to bushels: Multiply total volume in cubic feet by 0.7786.
- Estimate stored weight: Multiply bushels by the grain test weight to estimate the total stored mass.
Grain Bin Calculator Formula
| Variable | Meaning | Unit |
|---|---|---|
| Volume | Total geometric storage volume of the bin | ft³ |
| 0.7786 | Conversion factor from cubic feet to bushels | bushels per ft³ |
| Test weight | Weight per bushel for the stored grain | lb/bu |
Use the worked examples below to check how the formula behaves with real values. If the result looks unexpected, verify the unit assumptions and the meaning of each variable before interpreting the answer.
Worked Examples
- Radius: 18 ft
- Height: 30 ft
Result: Cone capacity is about 7,933 bushels.
This reflects the Omni cone example using the round-section capacity formula.
- Diameter: 36 ft
- Wall height: 30 ft
Result: Straight-wall volume is about 30,536 ft³ and capacity is about 23,775 bushels.
This uses the cylinder formula before any roof or hopper adjustments.
- Length: 40 ft
- Width: 30 ft
- Height: 15 ft
Result: Volume is 18,000 ft³ and capacity is about 14,015 bushels.
Rectangular storage can be approximated with the same bushel conversion factor.
How to Interpret Your Results
| Range | Meaning | Action |
|---|---|---|
| Higher bushel total | Larger storage capacity | Check loading limits, aeration design, and test-weight assumptions before using the result operationally. |
| Lower test weight | Less total mass for the same bushel volume | Use the correct commodity test weight when turning bushels into pounds. |
Frequently Asked Questions
References
Last reviewed: March 13, 2026