Concentration Calculator
Choose mass concentration or molarity. For molarity, either enter the moles directly or enter mass together with the solute's molar mass and the calculator will find moles for you.
Last updated: September 26, 2026
Frequently asked questions
What is the difference between mass concentration and molarity?
Mass concentration is mass of solute per volume of solution (g/L). Molarity is amount of substance (moles) per volume (mol/L). They both describe how much solute is present, but in different units, and converting between them requires the solute's molar mass.
How do I find molarity if I only know mass?
Enter the mass and the solute's molar mass (from the Molecular Weight Calculator if needed), and leave the moles field at 0; the calculator computes moles = mass / molar mass for you.
How is this different from Cell Dilution?
Cell Dilution solves the C1V1 = C2V2 relationship for how to dilute an existing stock to a target concentration. This calculator computes a concentration directly from mass or moles and volume, without a dilution step.
How is this different from Alligation?
Alligation finds the ratio needed to mix two different concentrations to hit a target in between. This calculator computes a single solution's concentration from its composition.
Can I use this for very dilute solutions?
Yes, the arithmetic is the same at any concentration, though at very high concentrations the assumption that volumes add ideally can break down.
What is molality, and does this calculator use it?
Molality is moles of solute per kilogram of solvent, not per volume of solution. This calculator computes molarity and mass concentration, both volume-based; for molality-based calculations see the Boiling Point Elevation Calculator.