Chess books are full of positions that deserve more than a glance: the moment a game turned, an exercise at the end of a chapter, a line the author dismisses in half a sentence. With ChessWOW you photograph the diagram, check the recognized board, and then work with it like any other position. The engine runs on your device, so this works at a desk, in a library or on a train.
Why scanning beats setting up by hand
Setting up a diagram on a real board or in an app takes a minute or two and invites small errors. A pawn on the wrong file, a missing bishop, and the analysis is about a different position. A scan takes seconds. Your job shrinks to comparing the board with the page, which is faster and catches more mistakes, because you look at the whole position at once.
How to scan a diagram in four steps
- Step 1
Lay the book flat and use good light. Daylight or a lamp from the side works best. Light from directly above can cause a glare on glossy paper.
- Step 2
Take the photo straight from above. Hold the phone parallel to the page so the diagram is square, not a trapezoid. Fill most of the frame with the diagram. The scanner shows corner markers; drag them onto the corners of the board if they are off.
- Step 3
Compare and correct. The recognized board appears next to your photo. Uncertain squares are marked. Tap any square to change a piece.
- Step 4
Set the side to move and start. Book diagrams usually say "White to move" or "Black to play" in the caption. Set the same in ChessWOW, and Stockfish 19 starts calculating.
A better way to use exercises
The engine can tell you the answer in a second. That is useful, but only after you have tried. A simple routine:
- Solve on the page first. Write down your main line and the opponent's best defence, not just the first move.
- Then scan and compare. Look at Stockfish's best move and the second and third lines. If your move is among them with a similar evaluation, your solution is sound even if the book gives another.
- Play the critical line out. From the scanned position, play against Stockfish and see if you can convert the advantage. Many exercises are easy to start and hard to finish.
- Save the ones you missed. Every scan stays in your library, so you can return to it a week later and try again.
- #11. Nf7#
- −3.01. Kf2
- −3.01. Nf3
Checking analysis in older books
Many classic books were written before strong engines existed. Sometimes an annotation says a move wins when it only draws, or calls a position equal when one side is clearly better. When a line seems strange, scan the diagram, step through the author's moves on the board and watch the evaluation. Treat the result as a second opinion, not a verdict on the author. Engines judge concrete positions; authors often explain plans that an evaluation number does not show.
Magazines, printouts and PDFs
The same steps work for chess magazines, club newsletters and printed exercise sheets. For e-books and PDFs on a tablet or computer, a screenshot is even cleaner than a photo; see analyze a chess screenshot. Very small diagrams, heavy shadows near the spine of a thick book and unusual piece designs make recognition harder. If the result needs many corrections, the chess board editor lets you place pieces directly.
Questions and answers
Does ChessWOW recognize diagrams from any chess book?
It works with printed 2D diagrams in the usual book and magazine styles. Unusual piece designs, tiny diagrams or strong glare can cause errors, which you correct with a tap.
The diagram is curved near the spine. What can I do?
Press the page flat, take the photo from straight above, and adjust the corner markers to the edges of the board.
How do I know whose move it is?
Book diagrams usually state it in the caption. Set the same side to move in ChessWOW before the analysis starts.
Can I photograph a real board on the table?
ChessWOW is made for 2D boards: screens, screenshots and printed diagrams. For a position on a real board, use the chess board editor.
Are my photos stored or uploaded?
The scan is saved in your library on your device. Photos are not uploaded.
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