Dry fertilizer Amount Calculator

How to Estimate Fertilizer Purchase Amount Using CalculatedAG.com

It is important to know how much fertilizer is needed before you purchase a large amount; you do not want to be left with too much, or even worse, not have enough. To determine how much dry fertilizer you need to purchase or obtain based on the size of your field and your desired application rate, follow these steps:

1. Enter Fertilizer Nutrient Percentages
   Input the percentage of Nitrogen, Phosphorus, and Potassium (NPK) in your fertilizer. These percentages are typically found on the fertilizer packaging and will help calculate the total fertilizer required for your field.


2. Specify Desired Spread (Application Rate)
   Input how much fertilizer you want to apply (in pounds) per unit area. You will also need to specify the unit for this rate (e.g., per 1,000 square feet or per acre).


3. Select Application Unit (Square Feet or Acres)
   Choose whether you are applying fertilizer per square foot or per acre. This ensures the calculation is adjusted based on your application unit.


4. Input Total Land Area
   Enter the total land area to which the fertilizer will be applied. This is usually measured in acres or square feet.


5. Calculate Fertilizer Amount Needed
   Click the "Calculate" button. The tool will compute how much total fertilizer is needed to cover the entire area based on your desired spread (application rate), the NPK percentages, and the total land area.

For the most accurate results: Ensure the fertilizer's NPK ratio matches the product you plan to use, and accurately measure your land area for precise calculations.

The formula being used only works properly with nitrogen based fertilizers utilizing N-P-K ratios.