SO4 Equivalent Rate Calculator

Convert sulfur supplied from other sulfur fertilizers into an equivalent SO4 Pelletized Gypsum rate.

At the bottom of the page is a printable cheat sheet reference table showing the equivalent SO4 Pelletized Gypsum rate for common sulfur rates supplied by other products.

Inputs

Summary

This calculator converts sulfur supplied from another product into the equivalent SO4 Pelletized Gypsum rate needed to supply the same sulfur amount.

ATS values entered as gal/acre use a density assumption to convert gallons to pounds before calculating sulfur supplied.

Elemental sulfur options are shown separately as 80%, 85%, and 90% sulfur to match the selected formulation.

SO4 Needed to Supply Equivalent Sulfur
176 lb/acre
Based on Ammonium Sulfate (AMS)
Based on the sulfur supplied by the selected other product, the calculator converts that sulfur amount into the equivalent SO4 Pelletized Gypsum rate.

Calculation breakdown

Other product
Selected fertilizer source
Ammonium Sulfate (AMS)
SO4 sulfur analysis
Built-in assumption
17.0% S
Other product rate
Entered product rate
125.0 lb/acre
Sulfur supplied
Used for conversion
30.0 lb S/acre
SO4 equivalent rate
Sulfur ÷ 0.17
176 lb/acre