Start / Grain and storage / Grain grading and drying
Enter the gross weight, impurities, and measured moisture to find out the net weight at standard moisture and the bags paid.
Pre-sizing and estimating tool: the results do not replace a design, calculation, or report signed by a qualified professional, nor verification against the applicable standards.
Kilos deducted for impurities and moisture in the load you entered.
Weight at standard moisture for each load moisture; the dot marks yours, and the dotted line marks the standard moisture.
Drag the controls to simulate data different from what you entered (from 30% less to 30% more) and watch the result change instantly.
Net weight at standard moisture for different moisture levels measured in the load, with the gross weight and impurities entered.
The calculation done in steps, with the values you entered.
The calculation memo gathers this page's inputs, results, equations, assumptions, and references, with fields for project, responsible person, and review. The full report also includes the charts and interpretations, in color. In the print window, choose Save as PDF.
Enter the gross weight of the load, the percentage of impurities and foreign matter, and the moisture measured at grading. Choose the product to load the standard moisture, or type the one in the contract. The calculator returns the net weight at standard moisture, the number of 60 kg bags, and the deduction for each factor.
Load of 30,000 kg of soybeans with 1% impurities and 15% moisture, to a 14% standard.
Weight without impurities = 30,000 × (1 − 0.01) = 29,700 kg. Weight at standard moisture = 29,700 × (100 − 15) ÷ (100 − 14) = 29,355 kg, or 489.2 bags of 60 kg. The total deduction is 645 kg, 2.15% of the gross weight.
The values below are trade references. What counts is the contract and the product standard in force on the sale date.
| Product | Typical standard moisture |
|---|---|
| Soybean | 14% |
| Corn | 14% |
| Wheat | 13% |
| Rough rice (paddy) | 13% |
If the moisture is well above the standard, calculate the water the dryer must remove in grain drying. To find out how much the net weight is worth in reais, use the production cost per hectare.
Multiply the weight without impurities by (100 − measured moisture) and divide by (100 − standard moisture). The result is the weight at standard moisture.
Because part of the weight is water. At standard moisture, the same grain weighs less than when wet, and the calculation keeps only the dry matter.
Multiply the clean weight by (100 − measured moisture) ÷ (100 − standard moisture). The result is the weight at standard moisture; the difference from the clean weight is the deduction.
The calculation first removes impurities from the gross weight and then corrects moisture on the clean weight. Check the order and the buyer's criteria in the contract.
It is the base moisture for marketing, at which the grain stays safe in storage. Above it, the weight is corrected and, in general, the buyer can also charge for drying.
No. The official standards, tolerances, and deductions come from the classification and the contract with the buyer. Only the weight correction for moisture and impurities is covered here.
Important notice: the Agrocalcs tools make estimates and preliminary sizing based on the data entered and on published engineering methods. They do not replace a design, a calculation report or a report signed by a qualified professional (CREA/ART), nor verification against the applicable technical standards and legislation, such as the Regulatory Standards of the Ministry of Labor. Material and fuel properties vary: check with the manufacturer or with analyses of your process before deciding. By using the site, you agree to the Terms of Use.
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