Use this calculator to …

Convert fertilizer recommendations between pounds per acre and pounds per square feet.

List alternative recommendations when fertilizer grades are not available.

Get recommendations based on the specific area to be fertilized.

Calculate fertilizer costs.

Fertilizer Calculator
R. Hitchcock and D. E. Kissel

The University of Georgia Fertilizer Calculator was developed to assist users whose fertilizer needs require adjustment from the standard soil test recommendation due to a change in units, availability of fertilizer products, and/or a difference in land size. The calculator ranks various fertilizer combinations, with the best getting the highest score.

You can use it to:

  • Calculate the weight of fertilizer materials to supply the amounts of N, P2O5, and K2O recommended by a soil test report.
  • Select recommendations in pounds per acre that are typical of agronomic crop recommendations or in pounds per 1000 square feet that are typical of homeowners reports such as for a home lawn.
  • Select fertilizer grades different from those given in the recommendation. This is useful when the fertilizer grades in the test report are not available locally.
  • Calculate the area of a garden or lawn given the dimensions and shape of the area to be fertilized.
  • Calculate fertilizer costs.
Step 1. Enter fertilizer requirements Step 2. Select available grades Step 3. Choose application rate and area
Fertilizer recommendations are given in:

Recommendation from
soil test report
pounds per acre
Choose from the list of commonly-available grades,
or add your own in N-P2O5-K2O format.
Show grades for:

Fertilizer grades
$ Cost per
If the area is unknown, what shape best describes the area to be fertilized?


Number of grades to use in recommendation:

Round recommendations to nearest: