Only Move

Henry Hemming

About this game

Only Move is a whole-board tsumego trainer for the game of Go (Baduk / Weiqi). Every position has exactly one winning move — find it.

Every problem is generated and verified by KataGo, the strongest open-source Go AI: one move wins the game, and every alternative loses. No ambiguity, no "good enough" answers — just clean reading practice.

164,000+ PROBLEMS ON TWO BOARDS
• About 123,000 problems on 9×9 and 42,000 on 13×13
• Difficulties from 20 kyu to 9 dan, on one shared scale
• Ratings are calibrated against real players' results, so a problem's rank means what it says

A RANK THAT TRACKS YOU
• Your rank is estimated from your recent solving history and updates after every problem
• See how your strength reads on the Go server scales you know (OGS, Fox, KGS, EGF and more)
• Problems are served at your level — you'll clear about 80% of them

LEARN FROM YOUR MISTAKES
• Failed problems come back for review right when you're about to forget them (spaced repetition)
• Optional reminders when reviews come due
• The app learns which kinds of moves trip you up and adjusts what it serves — and your stats page describes those weaknesses in plain sentences

EXPLORE EVERY POSITION
• After each attempt, review mode lets you play out variations with KataGo's evaluations
• Detailed stats: rank history with confidence bands, solving-time trends, and anonymous community comparisons

YOUR PROGRESS, EVERYWHERE
• A simple account code syncs your history and rank across devices — no email, no password, no sign-up
• Free, no ads

Whether you're taking your first steps on the 9×9 board or sharpening dan-level reading, there is always only one move.