Your Molecular Formula

List of allowed groups

Apply Gaussian:
Reference version:

(Peak Full Width at Half-Maximum)

Resolution = M / ΔM


Welcome to ChemCalc

If you are using our tools please don't forget to cite us:

ChemCalc: a building block for tomorrow’s chemical infrastructure. Patiny, Luc; Borel, Alain Journal of Chemical Information and Modeling 2013. DOI: 10.1021/ci300563h

Cheat poster: Get HELP on how to use chemcalc !

Our new tool: MS PolyCalc, the ultimate polymer distribution analyzer. To test with Google Chrome ! Desport JS, Frache G, Patiny L Rapid Commun. Mass Spectrom. 2019. DOI:

What would you like to do ?

Latest news ...

HELP! How to enter a molecular formula ?

This tool very flexible and you will see here after couple of syntax examples:

This program is the result of a collaboration between the Faculty of Chemistry of the Silesian University of Technology (Poland) and the University of Lausanne (Switzerland). ChemCalc has been presented on 5th International Electronic Conference on Synthetic Organic Chemistry.