The CMIP6 next generation (CMIP6ng) archive is an update to the raw CMIP6 archive as provided by the Earth System Grid Federation (ESGF). It introduces a range of additional checks for the processed variables and their main dimensions (time, longitude, latitude) as well as incremental optimizations in the file structure and consistency of the files from different institutions. It provides models in their native horizontal resolution and on a common 2.5°×2.5° longitude-latitude grid. Files are provided in monthly time resolution and as annual means calculated from the monthly means. In addition, selected variables are available in daily resolution. Here, the differences between the CMIP6ng and the raw CMIP6 archives are presented, the processing structure is detailed and a list of checks is given.