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Preview of RepCheck

RepCheck by patrik

Highlights the move where your game deviates from your opening repertoire on chess.com and lichess.org. Load your repertoire from a local PGN folder, paste PGN, or connect a RookHub server.

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About this extension
RepCheck analyzes your chess.com and lichess.org games against your
opening repertoire in real time, highlighting exactly where you went
off-book โ€” directly in the analysis view.

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”
FEATURES
โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”

โ€ข Deviation detection: The first move outside your repertoire is
highlighted in the move list.
โ€ข Gap display: Moves not yet covered in your repertoire are marked
separately.
โ€ข Chessable link: One-click search on Chessable for the deviation move.
โ€ข Supported platforms: chess.com/analysis, chess.com/game/review,
lichess.org/analysis.

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”
REPERTOIRE SOURCES
โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”
  1. Local PGN folder โ€” pick a folder of PGN files via the browser dialog.
    No upload, no cloud, everything stays on your device.
  2. PGN paste โ€” paste your repertoire directly into the settings panel.
  3. RookHub (optional) โ€” connect your own RookHub instance as a backend.
    Analysis runs server-side; the extension only sends the move list and
    receives annotations in return.

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”
PRIVACY
โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”

โ€ข No telemetry, no analytics, no third-party servers.
โ€ข In local mode, no data leaves your browser.
โ€ข In RookHub mode, the extension communicates exclusively with your own
self-hosted RookHub instance at the URL you provide.

โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”
SETUP
โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”โ”
  1. Open chess.com or lichess.org and navigate to a game analysis page.
  2. The RepCheck banner appears automatically โ€” click โš™ to open settings.
  3. Enter your RookHub URL and token and click "Connect" โ€” or select a
    local PGN folder.

Source code: https://github.com/kahalm/repcheck
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Permissions and data

Required permissions:

  • Access your data for www.chess.com
  • Access your data for lichess.org
  • Access your data for www.chessable.com
  • Access your data for chessable.com

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
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Version
1.8.0
Size
35.07 KB
Last updated
4 days ago (Jun 11, 2026)
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License
MIT License
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