The method and algorithm for determining total ozone column amounts (TOC) based on spectroscopic measurements of outgoing thermal radiation by IKFS-2 spectrometer (on-board ″Meteor-M No. 2″ satellite) are described. The algorithm is based on the artifi cial neural network method and satellite measurements of TOC using ozone monitoring instrumentation (OMI). Comparison of the results of TOC measurements by IKFS-2 spectrometer and by ground-based instruments (Dobson, Brewer, and M-124 ozonometers) are given. It is shown that systematic discrepancy between the results of satellite and ground-based measurements in most cases does not exceed 1%, and RMSD values are within 3.0–4.5%. The empirical assessment of random measurement errors in the determination of TOC demonstrates that Dobson and Brewer TOC measurement random total errors are ~1% (in direct solar radiation measurements mode), and OMI and IKFS-2 satellite measurements give 2.8 and 3.6% random errors, respectively.