Molarity Calculator

Molarity Formula

Worked Example

29.22 g of sodium chloride (M = 58.44 g/mol) made up to 1 litre:

1. c = m ÷ (M × V)
2. c = 29.22 ÷ (58.44 × 1)
3. c = 0.5 mol/L (M)

In µmol/L (µM): 500000 µmol/L (µM) · In nmol/L (nM): 500000000 nmol/L (nM) · Moles of solute n = m/M: 0.5 mol · Mass concentration m/V: 29.22 g/L

Molarity versus molality

Molarity is moles per litre of solution and changes slightly with temperature; molality is moles per kilogram of solvent and does not. For dilute water solutions they are nearly equal.

More Moles and Concentration Calculators

• Molar Mass Calculator

  M = Σ nᵢ Aᵢ

  nᵢ number of atoms of each element, Aᵢ its standard atomic weight (g/mol)

  Example: Sulfuric acid, H2SO4: Molar mass M = 98.072 g/mol.

  Open the molar mass calculator →

• Moles Calculator

  n = m / M

  n amount (mol), m mass (g), M molar mass (g/mol); particles N = n × Nₐ

  Example: 36.03 g of water (M = 18.015 g/mol): Amount of substance n = 2 mol.

  Open the moles calculator →

• Dilution Calculator

  C₁ V₁ = C₂ V₂

  C₁ stock concentration, V₁ stock volume, C₂ final concentration, V₂ final volume

  Example: Making 1 L of 0.1 M solution from a 2 M stock: Stock volume needed V₁ = 0.05 L.

  Open the dilution calculator →

Frequently asked questions

Sources

• The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures .

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.