Al2(SO4)3 — aluminum sulfate — means 2 aluminum atoms, then a group of 1 sulfur and 4 oxygen atoms repeated 3 times. A calculator that just adds up letter-by-letter without understanding parentheses gets this wrong.
Molar mass calculator, with an actual formula parser
This tool reads chemical notation properly — element symbols with subscripts, and parenthesized groups (including nested ones) multiplied by whatever number follows the closing parenthesis — the same way a chemistry textbook would read it.
Chemical formula weight calculator, checked against real compounds
Water (H2O) comes out to 18.015 g/mol, glucose (C6H12O6) to 180.156 g/mol, and aluminum sulfate (Al2(SO4)3) to 342.132 g/mol — matching standard reference values.
How to calculate molecular weight, element by element
Alongside the total, the element breakdown shows exactly which atoms and how many of each the parser found — useful for double-checking you typed the formula the way you meant to.
