How to prepare for a chess opponent
A practical way to get ready for your next tournament or online opponent in about twenty minutes, using their real games.
Short version: find the openings your opponent plays most, pick one line where they score badly or that suits you, check it with an engine, and play it once against a clone of them. Twenty minutes is enough.
Why opponent preparation works
Most club and junior players have a small repertoire and play it every game. If you know that your opponent answers 1.e4 with the Caro-Kann in nine games out of ten, you can walk into the game with a plan you have already checked, instead of spending twenty minutes of your clock on move six. Strong players prepare for every round. With the right tool it takes minutes, not hours.
Step by step
- Find your opponentOpen Opponent prep. For over-the-board events, search their name or FIDE ID. Chessmoose links the FIDE rating list to more than 1.1 million tournament games broadcast since 2020. For online games, type their Chess.com or Lichess username to load up to their last 1,500 games.
- Pick the right colour and time controlIf you will have White, look at their games as Black, and the other way round. Filter to classical or rapid if that is what you will play: people often use different openings in blitz.
- Read the opening treeThe tree shows every move they have played from each position, how often, and their score with it. On the board, arrows show all of their choices: the brighter the arrow, the more often they play it. On your moves, blue arrows show what other opponents have tried against them.
- Find a weak spotLook for a line they play often but score badly in, or a position where they spread over many different moves, which usually means they are not sure. Those are the places to steer the game.
- Check it with the engineTurn on the Stockfish 19 panel and the evaluation bar right in the prep view. Make sure your chosen line is sound and note the critical move where they usually go wrong.
- Play the clonePress Play vs clone. The clone plays your opponent's real moves, in the same proportions, for as long as their games reach the position, and then Stockfish takes over at about their rating. One or two games make the plan stick.
- Save the opponentPress Save opponent so their tree is one click away next time you are paired.
What to look for in the tree
| You see | What it usually means |
|---|---|
| One move played 80% of the time | A fixed repertoire. Prepare deeply against that single line. |
| Many different moves, none above 30% | They are unsure here. A good place to surprise them. |
| A frequent line with a low score | A known problem line for them. Aim for it. |
| Games that leave theory early | Prepare a solid plan, not long memorised moves. |
Common mistakes
- Memorising too much. Know one line and the ideas behind it. Long memorised lines are forgotten under tournament pressure.
- Ignoring time control. A player's blitz repertoire can be very different from their classical one.
- Preparing a line you do not understand. A slightly worse position you know well beats a "best" line you do not.
- Forgetting the other colour. If the pairing is not out yet, prepare a short plan for both colours.
Frequently asked questions
- Can I see what openings a FIDE player plays?
- Yes. Chessmoose has over 1.1 million over-the-board tournament games broadcast since 2020, linked to the FIDE rating list. Search a name or FIDE ID to see their opening tree as White and Black.
- Does it work for Chess.com and Lichess players?
- Yes. Type a Chess.com or Lichess username and Chessmoose loads up to their last 1,500 public games and builds the same opening tree, filtered by time control.
- Is opponent prep free?
- Yes. Opponent prep, the engine and the clone are free to use on Chessmoose, with no ads.
- How long should I prepare before a game?
- For a weekend tournament, 15 to 30 minutes per opponent is plenty: find their two or three main lines, pick one plan, and check it with an engine. Do not try to memorise everything.
- Is preparing against an opponent allowed?
- Yes. Preparing from public games before the round is normal and allowed. Using any outside help during the game is not.