How do you convert milligrams per liter to troy ounces per gallon?

1 milligram per liter = 0.000121703815 troy ounces per US gallon. So, multiply the number of mg per liter by 0.000121703815 to get troy ounces per US gallon.

Example, 500 (milligrams per liter) x 0.000121703815 = 0.0608519075 troy ounces per US gallon.