How to Convert PPM to MG/L
- 1). Write out the ppm value of your solution concentration, replacing ppm with units of milligrams per kilogram. For example, if your concentration value is 28 ppm, you would write out 28 mg per kg. Since there are 1,000 mg in a gram and 1,000 grams in a kg, the mg per kg of solution is the same as ppm.
- 2). Divide the mg/kg concentration value you just wrote out by 1,000 -- the number of grams in a kilogram -- to convert it into units of mg per gram. In the case of 28 mg per kg, you would calculate 28/1000 = 0.028 mg per gram.
- 3). Multiply the value you just calculated by the density of your solution, in units of grams per milliliter. This calculation will give you the solution concentration in units of mg per mL. If the density of the solution in the example was 1.08 grams/mL, your calculation would be 0.028 times 1.08 = 0.0302 mg/mL.
- 4). Multiply this latest value by 1,000, the number of milliliters in a liter. This will convert your concentration reading to units of milligrams per liter. The example would have a final value of 0.0302 times 1,000 = 30.2 mg/L.
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