Molarity Calculator
Choose what to solve, then enter solution volume, solute amount and a molar mass when mass is involved. Dilution mode keeps solute moles constant while changing concentration. Litres and millilitres are explicit to prevent a thousand-fold unit error.
Your result
How the calculation works
Molarity c=n/V in mol/L. Moles n=cV. Mass m=nM where M is molar mass in g/mol. Dilution uses c₁V₁=c₂V₂; solvent added is V₂−V₁.
Worked example
0.5 mol in 1 L gives 0.5 mol/L. At 58.44 g/mol, that amount has a mass of 29.22 g. Diluting 1 L of 0.5 M solution to 0.1 M gives 5 L final volume, adding 4 L.
Assumptions and limitations
Molar mass is supplied by the user. Dilution assumes additive volumes and no reaction or solute loss. Zero amount is permitted where applicable; solution volume and concentration divisors must be positive.
Educational calculation only. This tool does not assess compatibility, reaction hazards, safe mixing order, dosing, purity or laboratory practice.
Sources and editorial responsibility
Maintained by Renvoro Pty Ltd. Sources inform the methods and assumptions shown here; outputs have the limitations described on this page.
Method reviewed 2026-10-13. Calculation standards · Report an issue