This data set tabulates local electron densities and local magnetic field strengths magnetic field strengths obtained from Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) Active Ionospheric Sounding (AIS) mode ionograms. The electron density is obtained by measuring the increment in frequency between the plasma frequency harmonics, visible as bright vertical lines at low frequency and delay time in many MARSIS ionograms. Similarly, the local magnetic field strength is found by measuring the difference in delay time between electron cyclotron echoes, visible as bright horizontal lines at low frequency on many ionograms. Both the measured quantity and the derived result are included in the archive product. We also include a data quality flag giving the impression of the archivist as to how reliable each result is. This archive product includes only data from the nominal mission, which starts about orbit 1850 and ends on orbit 2539.