ChemicaLife
Molar Mass Calculator
Enter a chemical formula to calculate average molar mass, element counts and mass percentages. The parser supports nested groups and hydrate notation such as CuSO4·5H2O.
What this calculator supports
Element symbols
Standard symbols with numeric subscripts, including NaCl, C6H12O6 and Fe2O3.
Grouped formulas
Parentheses, square brackets and nested groups, such as Ca(OH)2 and K4[Fe(CN)6].
Hydrates
A middle dot or period with a leading multiplier, such as CuSO4·5H2O.
Frequently asked questions
Why might another calculator give a slightly different result?
Standard atomic weights can be intervals, and calculators may use different rounding conventions or isotope-specific masses. This tool uses conventional average atomic weights suitable for general calculations.
Does the calculator support ionic charge?
Charge does not materially change the conventional molar mass for routine calculations, but charge notation is not accepted in the formula field. Enter the neutral composition represented by the formula.
Can I use a product name instead of a formula?
No. Product names can refer to mixtures or different hydration states. Enter an explicit chemical formula.
Atomic-weight source and related tools
Values are based on conventional atomic weights published by the Commission on Isotopic Abundances and Atomic Weights. Bracketed representative mass numbers are used for elements without a standard atomic weight.