The current web calculator for stopping powers is a real time implemetation of the "SRIM Module.exe" included in SRIM 2013 code (SRIM Tutorials), i.e., the current tables are those provided by SRIM code.
Output table includes the electronic stopping power in units of Mev cm2/g (i.e., the mass electronic stopping power).
The lower energy limit is 1 eV
The higher energy limit is 5 GeV/nucleon
In SRIM treats gas targets are dealt differently from those solid. User can select the target as gas only for elemental gas targets: H, He, N, O, F, Ne, Cl, Ar, Kr, Xe, Rn.
In the present electronic stopping power to dose converter, the energy lost by the incoming particle is assumed to be fully absorbed by the medium - for instance, the medium is supposed to to be thick enough to fully absorb the kinetic energy of emitted delta rays - and the particle energy is almost constant while traversing the absorber.