Online PGN Cleaner & Formatter
Strip comments, format notation, and normalize your chess game files instantly. Perfect for cleaning database exports from Chess.com, Lichess, or ChessBase.
Illustration showing the difference between messy raw PGN and clean standard PGN.
What is PGN Cleaning?
PGN (Portable Game Notation) is the universal standard for sharing chess games. However, when exporting from engines like Stockfish or sites like Chess.com, the data often includes deep engine evaluations, timestamps, and nested variations that make it difficult to read.
Our PGN Cleaner uses chess.js to rebuild the game state and export a "normalized" version. This removes unnecessary clutter while preserving the core moves and headers (like White, Black, and Result).
Key Benefits
- Database Compatibility: Clean PGNs are much easier to import into ChessBase or SCID without errors.
- SEO Optimized Sharing: If you are a chess blogger, cleaner notation helps search engines index your moves.
- Privacy: Remove meta-tags like 'Site' or 'Date' if you want to share a training game anonymously.
Why Standardize Your Notation?
Professional chess preparation requires professional data management.
Avoid Import Errors
Messy comments can often crash lightweight PGN viewers. Standardization ensures 100% uptime for your tools.
Better AI Training
If you use LLMs to analyze your games, providing clean notation helps the model focus on the moves, not the timestamps.
Easier Collaboration
Coaches and students work best when looking at clear, concise notation without engine "noise".
Common Questions
Will cleaning PGN remove my moves?
No. The actual moves and result are preserved exactly. The PGN cleaner only strips out comments, NAG annotations, evaluation tags, clock times, and optionally variations.
Does this support multi-game PGN files?
Currently, the tool processes the first game in the input. For databases with many games, run the cleaner per game or paste them one at a time. Batch cleaning is on the roadmap.
Is my data stored on your server?
No. The cleaning runs entirely in your browser with JavaScript. Your PGN never leaves your device unless you choose to share or save it elsewhere.
Can I remove only variations and keep comments, or vice versa?
Yes. The cleaner exposes individual toggles so you can choose to strip comments, variations, NAG codes, or clock annotations independently.
Will the cleaned PGN import into Lichess, Chess.com, or ChessBase?
Yes. The output follows the standard PGN specification and is accepted by Lichess, Chess.com, ChessBase, Scid, and every common engine front-end.
How do I convert a heavily annotated PGN to plain moves only?
Paste the PGN, enable Strip Comments, Strip Variations, Strip NAG, and Strip Clock. Click Clean. The output is a minimal, machine-readable PGN ready for engines, GIF makers, or databases.