Molar Mass Calculator
Compute molar mass from a chemical formula. Supports common elements; multi-character symbols and subscripts.
Result
Molar mass
18.015 g/mol
Formula: H2O.
- H(1.008)×22.016
- O(15.999)15.999
Step-by-step
- Add: H(1.008)×2 = 2.016.
- Add: O(15.999) = 15.999.
- Total = 18.015 g/mol.
How to use this calculator
- Type the formula (case-sensitive: O ≠ o).
- Read molar mass.
About this calculator
Molar mass is the mass of one mole of a substance, in g/mol. For a molecule, sum the atomic masses of all atoms. H2O = 2 × 1.008 + 15.999 = 18.015. The calculator handles common formulas with single-letter and two-letter element symbols and integer subscripts. Parentheses and water-of-hydration aren't parsed; expand them yourself if needed.
Frequently asked
Because Co (cobalt) ≠ CO (carbon monoxide). Element symbols start with a capital letter; the optional second letter is lowercase.
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