Molar Mass Calculator
PROLook up or enter molar mass for common compounds and elements.
PhD Chemistry (Analytical), MRSC
Analytical chemist with 12 years in pharmaceutical QA, spectroscopy, and solution chemistry. Passionate about making chemistry accessible.
Unlock Molar Mass Calculator
Get full results, advanced insights and unlimited access with Numly Pro.
- Access this and 300+ professional calculators
- Advanced insights and detailed breakdowns
- Engineering, trading, clinical and chemistry tools
- Save calculations and track history
- Export results as PDF
- No ads — ever
NZ$9.99/month after trial · Cancel anytime
Related calculators
Molarity Calculator
Calculate molar concentration (mol/L) from mass, molar mass and volume.
Dilution Calculator
Find the final concentration or volume after diluting a stock solution (C₁V₁ = C₂V₂).
Stoichiometry & Reaction Yield
Calculate theoretical yield, actual yield and percent yield from a chemical reaction.
About the Molar Mass Calculator
Molar mass (also called molecular weight) is the mass of one mole of a substance, expressed in grams per mole (g/mol).
It equals the sum of the atomic masses of all atoms in the molecular formula. One mole contains 6.022 × 10²³ particles (Avogadro's number).
How it works
M = \sum (n_i \times A_i)
Tips to improve your result
- 1.
For ionic compounds, use the formula unit (e.g., NaCl) not the smallest ratio.
- 2.
Molar mass numerically equals relative molecular mass but has units of g/mol.