Enter the parts per million (ppm) into the Calculator. The calculator will evaluate the Grains Per Gallon. 

Grains Per Gallon Formula

GPG = PPM / 17.1


  • GPG is the Grains Per Gallons ((grains per gallon))
  • PPM is the parts per million (ppm)

To calculate Grains Per Gallon, divide the parts per million by 17.1

How to Calculate Grains Per Gallons?

The following steps outline how to calculate the Grains Per Gallon.

  1. First, determine the parts per million (ppm). 
  2. Next, gather the formula from above = GPG = PPM / 17.1.
  3. Finally, calculate the Grains Per Gallon.
  4. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

parts per million (ppm) = 70