What is Chess960?
The whole variant in plain terms: what changes, what does not, and the three constraints that leave exactly 960 positions.
Learn Chess960
Thirteen guides. Start with the rules if the variant is new to you, or with castling if that is the part that is bothering you, which it usually is.
Is Chess960 better?
The case for playing it, and the honest case against. What it costs a beginner, whether it is harder, and whether it makes you better at ordinary chess.
How to play Chess960
For someone who plays ordinary chess and has never played 960. Setting up, the one step people get wrong, and what to do on move one.
Castling in Chess960
The rule everyone gets stuck on. The king and rook always finish on the standard squares; only where they start moves.
Why exactly 960 positions
The arithmetic, done visibly: 4 x 4 x 6 x 10, and why the king and rooks have no choice left once the rest are placed.
Chess960 strategy and opening principles
What replaces opening theory when there is none, and what to look at on your own back rank before move one.
Chess960 tactics
Which tactical motifs actually occur in Chess960, measured against standard chess over 21,019 mined puzzles. Pins are twice as common; back-rank mates less than half.
Best Chess960 positions
There is no officially best position, so this characterises them by properties you can compute: most and fewest first moves, undefended pawns, corner rooks.
Chess960 vs standard chess
What is identical, what is not, and the preparation argument given fairly on both sides.
Freestyle Chess
Freestyle Chess is Chess960 under another name. The rules, why a second name exists, and what a new player or a spectator needs to follow it.
Freestyle Chess vs Chess960
They are the same game. What actually differs is the branding and the event conventions, and the naming mess is worth clearing up once.
Chess960 ratings and Elo
Why your 960 rating differs from your classical one, and how separate rating pools behave.
Chess960 glossary
SP numbers, X-FEN, the corner rook problem, and the rest of the vocabulary, defined once.
Where to start
If you have never played Chess960, read the rules and then roll a board on the position generator. Nothing else about the game changes, so you already know how to play it.
If you have played a few games and castling still catches you out, that has its own page: castling in Chess960. Every position page also states its own castling squares, so you can check the arrangement in front of you rather than working from the general rule.
If you want to get better at it, the answer is calculation rather than preparation. Strategy and opening principles covers what to look for, and the puzzle trainer drills it on real positions.