Concentration unit converter
M ↔ mM ↔ µM ↔ nM ↔ % ↔ ppm ↔ mg/mL ↔ g/L. Add the MW for molar ↔ mass.
Enter a concentration value — it is shown in every unit that can be derived.
Formula and how to use it
Concentration can be expressed in molar terms (M, mM, µM, nM) or mass terms (%, ppm, mg/mL, g/L), and converting between the two families requires the compound's molecular weight. Within the molar family the prefixes are powers of a thousand: 1 M = 1,000 mM = 10⁶ µM = 10⁹ nM.
Within the mass family, 1 g/L = 1 mg/mL and 1 % w/v = 10 g/L = 10,000 ppm (for dilute aqueous solutions). To cross families, use the bridge M = (g/L) ÷ MW: a 1 M solution of glucose (MW 180.16 g/mol) is 180.16 g/L, i.e. 180.16 mg/mL.
This converter shows the entered value in all eight units at once, with an optional molecular-weight field for the molar ↔ mass directions, so you can check a protocol's units without manual arithmetic.