Grain Drying Time Calculator

Work out grain drying time instantly with clear inputs, formula shown and shareable results.

About Grain Drying Time Calculator

Drying time is the mass of water to evaporate divided by the dryer's water removal rate. Water mass follows the shrinkage identity: lot weight x (initial MC - final MC)/(100 - final MC). The same identity gives the outturn weight, which is what the grain will actually weigh on the sale scale.

Formulas

Water to remove

Water (kg) = lot (kg) x (MC initial - MC final) / (100 - MC final)

Drying time

Hours = water to remove / dryer removal rate (kg/h)

Worked example

With the default values below, Grain Drying Time Calculator returns Drying Time of 6.70. Change any input above and every figure here is recalculated in your browser.

Inputs used

Grain Quantityminimum 0.01 tonnes: 10 tonnes
Initial Moistureaccepts 1–45 %: 20 %
Target Moistureaccepts 1–40 %: 13 %
Dryer Water Removal Rateminimum 0.1 kg water/hour: 120 kg water/hour

Results

Drying Time: 6.70
Water To Evaporate: 804.6
Dried Grain Outturn: 9.195
Weight Loss On Drying: 8.05%

Step by step

1Values used
2Water to remove
3Drying time
4Drying Time= 6.70
5Water To Evaporate= 804.6
6Dried Grain Outturn= 9.195
7Weight Loss On Drying= 8.05

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why is drying time longer in practice?

Removal rate falls as grain dries because surface moisture goes first and the remaining water must diffuse out of the kernel. Late-stage drying can be half the early rate, and high ambient humidity slows everything.

How fast can grain safely be dried?

Limit removal to about 1% moisture per hour for seed and malting grain to avoid stress cracking. Feed and milling grain tolerates faster drying with higher air temperatures.