GammonBase Desktop · Windows and Mac
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 — nothing you play is uploaded anywhere.
You will be asked to sign in first — the download is tied to your GammonBase account.
Free to install. Playing and analysing need a licence — see plans and prices.
Signed by Customation AS. The certificate is new, so Windows and Chrome may warn about it until enough people have installed it — the checksum below is how you confirm the file is ours.
Windows · 5.0 MB —
compare this against the file you downloaded:
Get-FileHash GammonBase-Desktop-0.1.11-windows-x86_64.exe
SHA-256 40e3151e012145af8e834920c5b952db7fa25e20e24d2f398cd10b99937d8d12Mac (Apple Silicon) · 6.9 MB —
compare this against the file you downloaded:
shasum -a 256 GammonBase-Desktop-0.1.11-macos-aarch64.dmg
SHA-256 b470f9b358b9c62ba0d3b3a5216e85ca8fe2503a22fc9180bc7c6babe0694bb8Mac (Intel) · 7.5 MB —
compare this against the file you downloaded:
shasum -a 256 GammonBase-Desktop-0.1.11-macos-x86_64.dmg
SHA-256 61207a3f552500f2e15694c0eefe4e7ce1e547045bfe41cb12ba37dea2c9267a
You can also check who signed it. On Windows, right-click the
installer and choose Properties → Digital Signatures;
on a Mac, run codesign -dv --verbose=2 against the app
inside the disk image. Either should name Customation
AS. Both checks are worth more than a browser's verdict:
they identify this exact build, whereas a warning only means the
certificate has not been seen often yet.
What you get
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.
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.
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.
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.
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.
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 licence
The app and the engines cost nothing to download, and your own matches stay open and exportable forever. Playing against an engine and having your decisions graded is what a licence unlocks.
The engines
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 long-standing free backgammon engine, as an analysis daemon.
GammonBase's house engine. Nineteen neural networks with a backgame-aware pair strategy, plus a one-sided bearoff database.
Getting started
On Windows it installs for your user only, so there is no prompt for administrator rights. On a Mac, drag it into Applications.
GammonBase offers on first run. One click, a few seconds — and you say where it goes if your system drive is tight.
Then open it in Review and find out what each position was really worth.
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.