Science

Molarity calculator

Molar concentration (mol/L) from mass, molar mass and volume.

  • Instant
  • Free
  • Private (processed locally)
  • No sign-up

ℹ️ C = n / V, with n = mass ÷ molar mass. Tip: get the molar mass with the “Molar mass” tool. 100% local.

Calculate a molarity

Enter the mass, the molar mass and the volume: the tool gives the molar concentration and the amount of substance.

Example (NaCl)

InputValue
Mass58.44 g
Molar mass58.44 g/mol
Volume1 L
Molarity1 mol/L

Exact calculation. 100% local.

Frequently asked questions

Which formula?

C = n / V, where n (mol) = mass (g) ÷ molar mass (g/mol) and V is the volume in liters.

Where to find the molar mass?

Use our “Molar mass” tool: it computes the molar mass from the chemical formula.

What about dilution?

For a dilution use C₁V₁ = C₂V₂; this tool gives the starting concentration.