Grams to Moles Calculator

Convert grams to moles using molar mass. Enter mass in grams and molar mass (g/mol) to find the number of moles.

g
g/mol

MOLES

0.9992 mol


ATOMS / MOLECULES

6.0171e+23

FORMULA

n = m / M

Common Molar Masses

SubstanceFormulaMolar Mass (g/mol)
WaterH₂O18.015
Carbon dioxideCO₂44.009
Sodium chlorideNaCl58.443
GlucoseC₆H₁₂O₆180.156
EthanolC₂H₅OH46.068
Oxygen gasO₂31.998

💡 How to Convert Grams to Moles

What Is Molar Mass?

Molar mass is the mass of one mole of a substance, measured in grams per mole (g/mol). It numerically equals the sum of the atomic masses of all atoms in the substance's chemical formula. You can find atomic masses on the periodic table or use our molar mass calculator.

How to Convert Grams to Moles

Grams to Moles Formula

n = m / M

Where:

  • n = number of moles
  • m = mass in grams (g)
  • M = molar mass (g/mol)

For example, to find how many moles are in 36 grams of water (H₂O, M = 18.015 g/mol):

n = 36 / 18.015 = 2.0 moles

Those 2 moles contain 2 × 6.022 × 10²³ = 1.204 × 10²⁴ water molecules. Use our atoms to moles calculator to convert between particles and moles.

Common Molar Masses

Water (H₂O): 18.015 g/mol. Table salt (NaCl): 58.44 g/mol. Glucose (C₆H₁₂O₆): 180.16 g/mol. Carbon dioxide (CO₂): 44.01 g/mol. Oxygen gas (O₂): 32.00 g/mol. You can use these values in molarity or theoretical yield calculations.

18 grams of water = 1 mole = 6.022 × 10²³ molecules. Use the periodic table to find molar mass.

Grams to Moles Calculator FAQ