Your Chess.com and Lichess games. Together.
ChessSum is for players whose chess history spans several usernames or platforms. Connect the accounts you choose, import their public games and view one combined history. Keep your own accounts separate from players you follow; adding an opponent for analysis does not add their games to your personal results.
Understand what your numbers include
Compare wins, losses, draws and activity over the same dates and time controls. A game imported through both participants is counted once in the combined history. Ratings stay in their original platform and time-control pools: a Chess.com blitz rating and a Lichess rapid rating are not averaged into a new rating.
Combine multiple accounts · Counting rules and import coverage
Review patterns across your games
Choose a batch of your imported games for Stockfish analysis. Completed reports connect recorded mistakes to a small set of learning priorities, evidence and relevant practice. Optional AI explanations describe those findings; they do not replace the chess engine or guarantee improvement.
See the analysis workflow · View an illustrative combined dashboard
Know a player before the first move
Enter an opponent's public username to create a saved report about that player. See their recorded rating history, most-played openings and results. Start with a real game in the replay player, then open a matching lesson or explore the move statistics. The report is independent of the person reading it.
How player analysis works · Explore openings and example games
Choose what to share
Accounts, reports, messages and private PGN uploads are not automatically published. You can create a share link for an eligible report from public online games. Search visibility is a separate choice. Revocation disables the page on ChessSum; copies already downloaded or held by other services cannot be recalled.
Frequently asked questions
Can I connect several accounts on the same platform?
Yes. You can add multiple Chess.com accounts, multiple Lichess accounts or a mixture. Link only the accounts you intend to group; ChessSum does not infer common ownership from similar names.
Does ChessSum move my games between platforms?
No. ChessSum imports available public game records into its workspace. Your original accounts, ratings and games remain with their source platform.
Can someone read my private preparation?
Creating a preparation requires signing in and it stays private until you choose to share. Uploaded or mixed-PGN preparations remain private. A person receiving a shared report can read that saved version without starting a new analysis.
Will a shared report appear in Google or AI answers?
Published full reports are automatically eligible for search discovery when they meet our content-quality checks. Anonymous summaries stay out of search. Search engines and AI services decide what they crawl, index and cite; inclusion is not guaranteed.