Local-First Analysis
Your PGNs never leave your device. All analysis is powered entirely in your browser using an optimized WebAssembly build of Stockfish 18.
Stop solving generic puzzles.
rt2k analyzes your actual games using Stockfish 18, detects your personal "leaks", and generates targeted puzzles to help you master the patterns holding you back.
Leak Detection
We categorize your mistakes into Opening, Conversion, Blunders, and Imbalances so you know exactly what is bleeding your ELO.
Custom Puzzles
Don't just look at engine lines. We generate playable puzzles straight from the critical moments of your own games.
Frequently Asked Questions
Do I need to create an account?
No. rt2k uses your browser's IndexedDB to store your game history and analysis completely offline.
How is this different from Lichess or Chess.com?
Instead of giving you random tactical puzzles, rt2k builds puzzles from the exact positions where you made mistakes in your actual games.