GammonBase Desktop · Windows and Mac

Play it. Transcribe it.
Find out where it went wrong.

Play a full match against GNU Backgammon or Open Sage at the strength you choose. Record any game move by move — one you are watching, or one you are replaying. Then have every checker play and every cube decision graded: PR, error rate, and the eXtreme Gammon and GNU Backgammon skill tiers side by side. All of it on your own machine, with no account needed to analyse.

No build published yet
The first release is on its way.

What you get

Everything between the first roll and knowing better next time.

A real opponent

Pick GNU Backgammon or Open Sage, pick a strength, and play a full match — cube, Crawford, doubles, bear-off. No invented personalities: the engine you play against is named on screen, and it is the same engine that grades you afterwards.

The scorecard

PR and error rate for both players, with the eXtreme Gammon and GNU Backgammon skill tiers side by side, an estimated Elo, and the checker/cube split — per game or across the whole match.

Straight to the blunders

Step from one costly decision to the next. See what you played, what the engine wanted, and exactly how much equity the difference cost — with the ranked alternatives underneath.

Watch the match turn

An equity graph across the whole match and your PR as it develops, so the game where it slipped away is obvious at a glance — and a live PR while you are still playing.

Games you didn't play

Transcribe any match — one you are watching, or one you are replaying from a record — and it is analysed exactly like a game you played. You enter the rolls for both sides; the screen is built for keyboard speed and stays deliberately silent while you work.

It stays on your machine

Every match is saved locally the moment you start it, so you can close the app mid-game and pick it up later. Nothing needs a server to play or to analyse.

The engines

Free software, kept at arm's length.

GammonBase plays and analyses through separate engine programs. They are not in the installer and not behind any account: the app fetches them itself from Settings → Engines on first run, and you choose which drive they land on.

The engine catalogue is not reachable right now. The app fetches it directly, and will show what is available.

Getting started

Three steps, about two minutes.

  1. 1

    Run the installer

    On Windows it installs for your user only, so there is no prompt for administrator rights. On a Mac, drag it into Applications.

  2. 2

    Let it fetch an engine

    GammonBase offers on first run. One click, a few seconds — and you say where it goes if your system drive is tight.

  3. 3

    Play a match, or transcribe one

    Then open it in Review and find out what each position was really worth.

Get it on your machine.

Windows 10 or 11, or macOS 10.15 and later. 64-bit. The engines are free and come separately.

The Windows certificate is new, so Windows and Chrome may warn about it until enough people have installed it — choose More info → Run anyway, and use the checksum above to confirm the file is ours. The Mac build is notarized by Apple, so it opens without a warning.