This grams to moles calculator converts a substance's mass into moles using its molar mass, and shows the matching particle count.
Chemistry
Grams to Moles Calculator
Convert mass to amount of substance and particle count with molar mass.
Calculator
About this calculator
Formula notes
n = m / M, where m is mass in grams and M is molar mass in g/mol. Particles = n × 6.02214076×10²³ (Avogadro's number).
Worked examples
- Example: 18.015 g of water (M = 18.015 g/mol) is exactly 1 mol ≈ 6.022×10²³ molecules.
- Using a molar mass of 58.44 g/mol, 11.688 g of NaCl corresponds to 0.2000 mol before any purity correction.
How to use it
- Enter the mass in grams.
- Enter the molar mass (or compute it with the molar-mass tool).
- Read the moles and the particle estimate.
Frequently asked questions
Where do I get the molar mass?
Sum the atomic masses from the periodic table, or use the molar-mass calculator first.
Is a mole a mass or a count?
A count: 6.022×10²³ particles. Its mass in grams equals the molar mass.
Limits and interpretation
- The result is only as accurate as the molar mass and measured sample mass entered.
- Hydrates, mixtures, and impure samples require the correct chemical form and composition rather than the anhydrous compound value.