The Meteor 3/total ozone mapping spectrometer (TOMS) data set has been reprocessed using the version 7 TOMS total ozone algorithm and a recalibration of the TOMS instrument using in-flight and revised laboratory data. To provide continuity for the analysis of long-term trends, the absolute calibration of Meteor 3/TOMS was adjusted so that the measured radiances closely matched Nimbus 7/TOMS. The residual bias in ozone is less than 1% and shows no significant latitudinal or seasonal dependence. The calibration procedure and the differences between the current and previously used calibrations are discussed. Problems in the Meteor 3/TOMS data set caused by chopper wheel synchronization problems are described, and comparisons of the resulting data with version 7 of the Nimbus 7/TOMS data are presented.¿ 1997 American Geophysical Union