About this tool
Type a chemical formula such as H2O, Ca(OH)2 or C6H12O6 and get its molar mass in g/mol with a per-element breakdown; it runs entirely in your browser using IUPAC standard atomic weights.
Frequently asked questions
Are parentheses and groups supported?
Yes — nested parentheses, brackets and braces with multipliers are parsed, so formulas like K4[Fe(CN)6] are handled correctly.
What happens with an invalid symbol?
If the formula contains a symbol that is not a real element, an error message names the unknown symbol so you can fix it.