PPM calculator
ppm = (mass solute ÷ mass solution) × 10⁶, plus mg/L ↔ ppm ↔ % conversions.
Use the same mass unit for both (e.g. mg solute in g solution is not valid — convert first). 1 mg/L ≡ 1 ppm for dilute aqueous solutions.
Enter both masses (same unit) to see the concentration in ppm.
Formula and how to use it
Parts per million expresses a very dilute concentration: ppm = (mass of solute ÷ mass of solution) × 10⁶. For dilute aqueous solutions the density is effectively 1 kg/L, so 1 ppm equals 1 mg/L — the identity that makes ppm so useful in water, environment, and pharmaceutical analysis.
Converting to percent: 1 % = 10,000 ppm (1 part in 100 versus 1 part in 10⁶). So 500 ppm is 0.05 % w/v, and a 0.9 % saline solution is 9,000 ppm. Percent w/v means grams of solute per 100 mL of solution; percent v/v means millilitres of liquid per 100 mL.
This calculator converts between ppm, mg/L, % w/v, and % v/v, and also computes ppm directly from a solute and solution mass — the definition behind the unit.