Chemistry
Grams to Moles Calculator
Convert a mass in grams into moles using the molar mass of the substance, and see how many particles that represents.
Your inputs
Change any value to update the result instantly.
Amount of substance
1 mol
Millimoles
1,000 mmol
Particles present
6.0221 × 10²³
Mass check (n × M)
18.015 g
Molar mass must be greater than zero. Use the mass of the pure substance, not of a solution.
What this calculator does
Converts a mass in grams into an amount of substance in moles using the molar mass.
What your result means
The headline is the number of moles present; the particle count shows the same amount on the atomic scale.
Formula and working
n = m ÷ M
- 1
Collect the inputs
Mass of the sample (m) = 18.015 g; Molar mass (M) = 18.015 g/mol
- 2
Apply the formula
n = m ÷ M
- 3
Result
Amount of substance = 1 mol
Frequently asked questions
Symbols and assumptions
- m
- Mass in grams
- M
- Molar mass in g/mol
- n
- Amount of substance = m / M
- • The sample is the pure substance whose molar mass you entered.
Sources and review
Reviewed 2026-09-22 · Next review 2027-09-22
- • Impurities, hydrate water or solvent mass will make the result too high.
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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