The stats API exposes the best usage statistics in the improved output format invented by @pkmn/stats converted from the legacy statistics information found at Each available format gets its own resource under /stats/FORMAT.json e.g, /teams/gen9ou.json.

The "best" statistics for each format are defined to be the latest statistics from the cutoff used for tiering that meets a certain minimimum number of battles, i.e., effectively capturing the data from when the format was last seriously contested.

Note that because the output is converted from legacy statistics the caveats mentioned regarding legacy conversion apply:

A legacy version of Statistics is produced which does not have unique, wins or stats fields but retains the happinesses and spreads fields (rounded and respecting cutoffs appropriately) instead.

This may change in the future if and when @pkmn/stats is adopted by Smogon University.

A /stats/index.json resource exists which is a mapping from each valid format ID to a 2-tuple containing the number of uncompressed and gzip-compressed bytes each resource contains.