Mass Concentration to Molar Concentration Converter

Mass concentration expresses the amount of solute as mass per unit volume (e.g., g/L), while molar concentration expresses the amount of solute as moles per unit volume (e.g., M or mol/L). Molar concentration is often more useful for chemical calculations as it relates to the number of molecules. See also our Raoult's Law Calculator.

To convert mass concentration to molar concentration, divide the mass concentration by the molecular weight: Molarity (M) = Mass concentration (g/L) ÷ Molecular weight (g/mol).

Molecular weight is the sum of the atomic weights of all atoms in a molecule, expressed in g/mol or Da (Daltons). You can find molecular weights on chemical databases like PubChem, supplier catalogs, or calculate them from the molecular formula.

Molar concentration allows chemists to work with equal numbers of molecules or formula units, making stoichiometric calculations easier. It's essential for understanding reaction ratios, equilibrium constants, and solution properties that depend on particle number rather than mass.

Common units include M (molar = mol/L), mM (millimolar = 10⁻³ M), μM (micromolar = 10⁻⁶ M), nM (nanomolar = 10⁻⁹ M), and pM (picomolar = 10⁻¹² M). The choice depends on the concentration range of your solution.

Yes, this calculator works for any compound as long as you know its molecular weight. It's commonly used for small molecules, proteins, DNA, and other biological or chemical compounds in laboratory settings.

For compounds that dissociate (like salts), the calculator gives the concentration of the parent compound. If you need the concentration of individual ions, you'll need to multiply by the number of ions produced per molecule and account for the degree of dissociation.