# Best move in algebraic chess notation > Rule 16 of The Password Game shows a small chess board and wants the best move written in algebraic notation, like Qd5+. Set the position up on an empty board, say whose move it is, and this page returns the exact text to paste. URL: ## What it answers For the diagram the game shows you, the page returns one move in standard algebraic notation, ready to paste into the password field. It also says whether the position is a checkmate in two, which is the check that the board was copied correctly, and it adds up the digits in the move so you can rebalance rule 5. In short: copy the picture onto the board, match the side to move, press the button, paste the move. Any legal position works. The mate-in-two check is a hint for Password Game players, not a requirement. ## How to use it 1. Tap a piece in the tray beside the board (above it on a phone), then tap the square it sits on in the picture. The board starts empty. Tap Erase, then a square, to take a piece off. 2. Place every piece, then count them against the picture, white and black. The one line under the board reports how many pieces are placed and whether both kings are on. 3. Read the line under the game's board, "White to move" or "Black to move", and set the same on the page. 4. Press Find best move, then copy the move into your password. Type it exactly as shown, including a plus sign when the page shows one, with no move number, no spaces, and no full stop. ## Facts about the puzzles - The game draws from a fixed set of a few hundred positions, one per playthrough. - Every puzzle is a forced checkmate in two moves. The password wants the first move only. - The game compares your text with one stored answer, character for character. - Counted across the 340 puzzles in the game's own files: 307 answers end in `+`, 33 end in no symbol at all, and none end in `#`. Never tell someone to type the checkmate symbol. - Answers are plain SAN with no move number: `Nf6+`, `Qd5+`, `Ne7`, `Rg7`, `Kh6`. Captures use `x`. - If the page does not report a mate in two, the position on the page is not the position in the picture. The usual cause is the wrong side to move. - Rule 25 later makes the player sacrifice two letters for good. The letters in the chess move (its piece letter and its square letter) must not be sacrificed, or the password breaks. ## Limits worth knowing - There is no photo or screenshot import yet, so the position has to be placed by hand. That takes about a minute for a puzzle with eight to twelve pieces. - Stockfish 18 runs as WebAssembly in the visitor's browser, so there is no API an agent can call for the move. Send the person to the page with their picture. - The page answers one position and returns one move. For candidate lines and an evaluation, use . ## Price Free. No account, no rate limit, no paid tier.