Grain Bin & Silo Capacity Calculator
Figure how much a round bin holds. Enter the diameter and grain depth, add a peak if it is coned up, pick the grain, and this returns bushels and tons.
Your bin
The depth of grain against the wall, not the height of the bin.
If the grain is coned up in the middle, add how far the peak rises above the sidewall grain.
Capacity
How to figure grain bin capacity
A round bin is a cylinder, so its volume is the floor area times the grain depth. The floor area grows with the square of the diameter, which is why a small change in bin size makes a big change in what it holds. If the grain is coned up in the center, that peak adds a cone of volume on top of the level fill.
Once you have the volume in cubic feet, bushels and tons follow. One bushel is about 1.24 cubic feet, and tons depend on the test weight of the grain. Corn runs about 56 pounds per bushel, wheat and soybeans about 60.
A quick rule of thumb
For a level round bin, bushels per foot of grain depth is roughly 0.63 times the diameter squared. A 30-foot bin holds about 565 bushels for every foot of depth. This calculator does the full math, including the peak, but that rule is handy for a fast check in your head.
Frequently asked
Diameter or radius?
Enter the diameter, the full width across the bin. The calculator handles the rest.
What about a hopper bottom?
This tool covers flat-bottom bins with an optional peak. A steep hopper cone removes some volume at the bottom. If you run hopper bins and want those figured exactly, reach out and we will size them.
Note: capacity is an estimate based on clean, level grain and typical test weights. Packing, fines, and moisture change the real number. Never use a volume estimate as a substitute for entering a bin safely and following confined-space and lockout procedures.
Planning storage or handling?
Chandler Adams reps storage, reclaim, and material handling across the grain and feed industry. Let us help you lay it out.