Enter the formula and press "calculate" to work out the molecular mass, the number of moles in 1 g and the percentage by mass of each element. This calculator can be downloaded for off-line use - see below.
Chemical symbols are case specific and should be entered correctly to prevent ambiguity - for example, Fe will work correctly but FE and fe will not.
You can use up to 12 different elements and brackets () and  in your formula.
This calculator can be downloaded as a zip file for off-line use. The zip file contains a simplified webpage and a folder containing the required mathematical functions. Download the zip file by clicking on the link below, unzip it and extract the files into a folder on your computer. The webpage can then be opened directly on your computer for off-line use.
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