Rating comparisons have been updated! For the chess.com and USCF columns, I had access to a list of thousands of players with chess.com and USCF ratings. The list was then subset down to only players who were active in the last 45 days and have played over 25 games. FIDE ratings used a formula from Mark Glickman to convert USCF to FIDE ratings. Chessgoals.com survey data was used to build the lichess columns.
Most of the comparisons involve using a 2nd order polynomial with chess.com blitz serving as the independent variable, and the dependent variable will be one of the columns to the right.
Here’s an example of the chess.com blitz vs USCF comparison: