Skip to content
Calculation Machine

Molarity Calculator

Moles, mass and concentration for any solution.

Reviewed by the Calculation Machine team · How we check our maths

Your values

ⓘ Live results

Results
Molarity
1 mol/L
Moles of solute
1 mol
Millimolar
1000 mM
Mass percent (aqueous, approx)
5.844%

Working

  1. 1moles = 58.44 ÷ 58.44 = 1
  2. 2M = 1 ÷ 1 = 1

Quick answer

Molarity is moles of solute per litre of solution: M = mass ÷ (molar mass × litres).

The formula

M = mass ÷ (MW × V)

Worked example

Worked example

Using the values the calculator loads with.

Inputs

  • Mass of solute58.44 g
  • Molecular weight58.44 g/mol
  • Solution volume1 L

Result

  • Molarity1 mol/L
  • Moles of solute1 mol
  • Millimolar1000 mM
  • Mass percent (aqueous, approx)5.844%

How to use the Molarity Calculator

  1. 1Enter the mass of solute in grams.
  2. 2Add the molecular weight.
  3. 3Enter the final solution volume in litres.

Frequently asked questions

Molarity vs molality?

Molarity uses litres of solution and changes with temperature; molality uses kilograms of solvent and does not.

How do I dilute a stock solution?

Use M₁V₁ = M₂V₂ — multiply the stock concentration by the volume taken and divide by the final volume.

About this calculator