As the EPFL Mass Spectrometry facility, we have developed over years multiple versatile and free Online Mass Spectrometry Tools for many different analytes such as small molecules, proteins and oligonucleotides. The open access EPFL MStoolbox is a compilation of all these tools that allow the analysis of High Resolution Mass Spectra directly from your web browser. This webpage provides guidelines and explanations for each tool and is targeted for both beginners and advanced MS users. The EPFL MStoolbox could be particularly useful for anyone working in the field of Mass Spectrometry but does not have access to commercial software for the data treatment. The use of any of our applications is totally free, but sharing and citing it is highly appreciated. If you want to be updated, follow us in twitter or linkedln.