Parts per million calculator

Reviewed by the CalculatorHub team, edited by James Graham. Method from NIST Chemistry WebBook. Last verified 2026-06-22.

The Parts per million calculator computes parts per million from the relation ppm = (solute/solution) * 1e6. It takes 2 inputs (solute mass, solution mass) and returns the ppm. These calculators are for chemistry students, laboratory technicians and anyone working through solution preparation, reaction quantities or the properties and structure of a compound, where the result decides how much of a substance to weigh out, what volume to make a solution up to, or what a given set of conditions implies for the substances involved. Enter your values below and the result updates instantly, and you can share a permalink that pre-fills the exact calculation. Get the units consistent before entering anything (moles against grams, mL against L, absolute temperature wherever a gas relationship calls for it), and where your inputs come from measurement, report the answer to the significant figures the least precise of them actually supports rather than every digit displayed. For example, with solute mass = 1, solution mass = 1000, the ppm works out to 1000, and the worked example further down the page shows every step so you can follow the arithmetic and reproduce it by hand. Reference data is from NIST Chemistry WebBook; the relation itself is a standard result of chemistry, and the figure above each result carries the date it was last verified. Many of the relationships here hold only under ideal or well-behaved conditions, so results can depart from bench reality with concentrated solutions, non-ideal gases, incomplete reactions or impure reagents, and no calculated figure replaces careful measurement and safe handling of the chemicals themselves.