Opening Explorer

Free, open-source online chess platform with zero ads, zero paywalls, and a full suite of play and training tools.

The world's largest chess platform, offering play, tactics, courses, game analysis, and live event coverage for all levels.

Comprehensive chess training site renowned for its tactics trainer, opening trainer, and large game database.

Online chess learning platform using spaced repetition to help players memorize openings, tactics, and endgames.

Massive historical game database with over 10 million games, player bios, a community forum, and a puzzle archive.

Free online database of millions of master games with a powerful search interface and opening statistics.

Human-like AI chess engine trained to predict human moves at specific Elo levels, ideal for realistic practice.

Free cloud database of over 40 million chess positions with optimal engine moves, built for opening research.

Personalized opening explorer that analyzes your own games from Lichess or Chess.com to show your actual opening stats.

Opening repertoire builder and trainer with spaced repetition, tailored to your Elo and designed for efficient memorization.

Free, open-source opening repertoire trainer using spaced repetition, compatible with any PGN repertoire file.

Interactive opening explorer that visualizes the most common paths through the opening phase as a decision tree.

Free chess training site combining spaced repetition for openings, blindfold tactics, and endgame practice.

Searchable chess game database with millions of games, an opening explorer, and player statistics.

YouTube channel by Stjepan Tomic with systematic opening repertoire videos and middlegame concept series.

An interactive force-directed graph of all 3,704 ECO chess openings, colored by volume.