About Chess Openings Lab
Chess Openings Lab is a free reference for club players learning openings. Every one of its 954 pages plays its line on a board you can step through, explains the plans for both sides, shows the traps and lets you drill the moves.
Who runs it
The site is published by Stellar Capital LLC, a small independent publisher in Stamford, Connecticut. Pages are written and maintained under the pen name Morgan Hale. We are not a chess federation or a titled coach and we don't claim credentials; the site is a reference you can check, with every source below.
Where the moves, numbers and words come from
- Moves and names. The 68 families and their named variations come from the lichess opening list, released into the public domain (CC0). No move on the site was typed by hand: every line, trap and engine continuation is replayed move by move by a chess rules engine, and a page whose moves fail that check is not published.
- Engine evaluations. Every position was analyzed with Stockfish 17.1 at depth 20, keeping its three best lines. Scores are in pawns from White's point of view. Each number on a page carries the engine and depth that produced it, and we never show an evaluation the engine didn't give.
- Results by rating. How often a line is played and how it scores come from rated blitz, rapid and classical games in the lichess game database for September 2025 (CC0), grouped by the players' average rating. Bands with fewer than 30 games are left out.
- Transpositions. When the same position is reached by more than one move order, one page covers it and lists the other orders, so there is one place to learn it.
- Traps. The 23 traps were each confirmed by the engine: the losing move really loses, and we say so when the trap only works if the opponent cooperates.
- The writing. The ideas, plans and advice are written for each line from its position, its engine lines and its results. A script checks that every move the text mentions exists in that position, and that sibling pages don't repeat each other. We don't copy annotations from books or databases.
Credits
Opening names and moves: lichess.org opening list (CC0). Game statistics: lichess.org open database (CC0). Engine: Stockfish (GPLv3), run on our own machines. Chess pieces: the "cburnett" set by Colin M.L. Burnett, used under its BSD license.
How the site pays for itself
The site is free. A paid tier of the repertoire trainer (unlimited reviews and sync) is planned. Some links to chess shops, books and courses may earn a commission once those programs approve the site; it never changes what we recommend. Display ads may appear on reading pages, never inside the trainer. Details: affiliate disclosure.
Corrections
If a move, a name or a statement looks wrong, please tell us with the page address. Pages are generated from one dataset, so a confirmed fix reaches every page that shares the problem.
Updated October 2026.