Molar mass calculator

Type a chemical formula — element symbols with optional subscripts, in parentheses to group. Get the molecular weight in g/mol plus per-element contribution.

Molar mass
0 g/mol
ElementAtomic massCountContribution%

How to enter formulas

  • Element symbols are case-sensitive: Co = cobalt, CO = carbon monoxide.
  • Subscripts use plain digits after the element: H2O, CO2, C6H12O6.
  • Use parentheses to group: Ca(OH)2, Fe2(SO4)3, Al2(SO4)3·18H2O — only the basic group syntax is supported here (no hydrate dot · multiplier).