The University of Illinois
Weed Science

Corn Herbicide Premix Calculator

It’s no secret that the introduction of novel herbicide active ingredients has slowed recently, but that at the same time a plethora of premix products has proliferated. Herbicide premixes often can be confusing with respect to component active ingredients, product equivalents, application rates, etc. This interactive table was designed to allow users to determine equivalent application rates of various corn herbicide premixes.

The first column lists the commercial or trade name of the herbicide and its formulation. The second column also provides the amount of active ingredient or acid equivalent of each component per gallon or pound of formulated product. The third column lists an application rate for each premix.  We attempted to select application rates that were representative for Illinois, but you may want to select a different rate (see below for directions).  The fourth column indicates how much of each active ingredient is applied at the rate listed in the third column.  Note that while rates of commercial products are usually expressed in ounces, pounds, pints, quarts, etc. of product per acre, active ingredients are usually expressed in units of pounds active ingredient or acid equivalent per acre. Finally, the last column lists product equivalents for each premix component when the premix is applied at the rate listed in the third column.  

The application rates listed in the tables are meant to be used as a reference; for some of these herbicides the application rates will vary depending on soil texture, organic matter, weed species and size, etc.  Always consult the respective herbicide label for appropriate application rates. 

All the cells in this table are active, that is, values can be changed in any cell. We suggest that you change numbers only in column D - "If you apply" (blue numbers). Entering your own values in this column (followed by pressing the “enter” key) will recalculate the amount of acid equivalent (shown in column G) and product equivalents (shown in column K) that would be applied at that product rate . By clicking on the “Refresh” icon for your browser, you can reload this webpage back to the default numbers. The table can also be expanded for easier viewing by clicking and dragging the bottom, right corner of the spreadsheet to a different size.

For more information on herbicide premixes see the article, "What's in that Premix?"


To use this Web page interactively, you must have Microsoft® Internet Explorer 5.01 Service Pack 2 (SP2) or later and the Microsoft Office 2003 Web Components.

See the Microsoft Office Web site for more information.

The University of Illinois

College of Agricultural, Consumer and Environmental Sciences
Crop Sciences| University of Illinois
University of Illinois Extension

Department of Crop Sciences