Lichess Standard Chess Games: 6.7 Billion Rated Matches

6,771,826,271 standard rated chess games played on lichess.org, updated monthly by Lichess as of October 2025. The collection is provided in Parquet format to facilitate large-scale computational analysis of game history rather than traditional PGN viewing.

Use Cases

• Statistical analysis of opening move success rates across 6.7 billion games
• Training neural networks for move prediction based on historical game sequences
• Longitudinal study of player rating distributions and Elo inflation over time

Strengths

• Contains over 6.7 billion individual game records
• Released under a CC0 1.0 Universal public domain license
• Provided in Parquet format for efficient querying with Polars or Dask

Limitations

• Marked as a work in progress with potential for breaking changes
• Optimized for analysis rather than standard PGN software compatibility

Provenance

Source

lichess.org

Collection Method

Aggregated from Lichess database dumps.

Freshness

Updated monthly from database dumps.

Geography

Global