Parts Per Million (PPM) Calculator

Convert between ppm, ppb, percent, mg/L, and μg/L for solution concentrations.

ppm

ppb

Percent (%)

mg/L

μg/L (ppb aq.)

How It Works

Enter a value in any concentration unit and all other units update instantly. For aqueous solutions, ppm ≈ mg/L because the density of water is 1 kg/L.

Formula

ppm = mg/kg = mg/L (dilute aq.) | ppb = μg/kg | 1% = 10,000 ppm

Examples

1 ppm = 1 mg/L = 1000 ppb = 0.0001% | 500 mg/L = 500 ppm = 0.05%

Frequently Asked Questions

What does ppm mean?

Parts per million (ppm) means one part of solute per million parts of solution by mass. In dilute aqueous solutions, 1 ppm ≈ 1 mg/L.

How do I convert ppm to percent?

Divide ppm by 10,000. For example, 250 ppm = 250/10,000 = 0.025%.

How do I convert mg/L to ppm?

For dilute aqueous solutions, mg/L = ppm. 50 mg/L = 50 ppm.