Polyglot Books

Polyglot is a widely used binary format for opening books (.bin files). Masterboard can import a Polyglot book into any repertoire, and export any repertoire back out as a .bin file for use in external engines and GUIs.

Importing a Polyglot book into a repertoire

1. Open the repertoire from the Openings page.
2. In the Moves panel header, open the dropdown menu (the ⋯ button).
3. Select Import Polyglot .bin…
4. Pick your .bin file using the file picker.
5. The moves from the book are merged into the repertoire’s variation tree.

Note: Polyglot books store only move statistics — annotations, comments, and NAG symbols are not preserved on import.

Exporting a repertoire as a Polyglot book

1. On the Openings page, open the dropdown menu on the repertoire row (the ⋯ button that appears on hover).
2. Select Export Polyglot .bin…
3. Adjust move weights if needed, then click Export .bin.
4. The file is saved to a location you choose and is compatible with Arena, Cute Chess, BanksiaGUI, and Scid vs. PC.

Where to get Polyglot books

Large free Polyglot books are available from several sources:

• Cerebellum — a broad, frequently updated free book maintained by the computer chess community
• Perfect 2021 — a large curated free book

Books can also be generated from PGN collections using tools such as polyglot (open source) or the book-building tools in SCID.