Updated 4 September 2026
What the Password Game is asking for
Your password must include the best move in algebraic chess notation.
The Password Game draws one of a few hundred fixed chess puzzles and asks for a single move. Every one of those puzzles is a checkmate in two moves, and the password wants the first of the two, written in algebraic notation. The game checks your text against one stored answer, character for character, so the move has to be exact.
Almost every answer ends in a plus sign. 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 #.
How to copy your board onto this page
The game gives you a picture. This page needs the same pieces on the same squares, and nothing else.
- Tap a piece in the tray beside the board (above it on a phone), then tap the square it sits on in your picture. Squares are named by the letter under their column and the number beside their row, so d5 is column d, row 5.
- Place every piece, then count them against the picture, white and black.
- Set White or Black to move, whichever the game says under its board.
- Press Find best move, then copy the move into your password.
How to read the answer
Every answer is one piece letter, sometimes a symbol, and the square the piece lands on. This is the whole alphabet you need to read one.
| Symbol | What it means |
|---|---|
| K | King. |
| Q | Queen. |
| R | Rook. |
| B | Bishop. |
| N | Knight. Not K, because the king already has that letter. |
| e4 | No letter at all means a pawn. This one is a pawn going to e4. |
| x | The move captures something. |
| + | The move gives check. |
| # | The move is checkmate. |
| O-O | Castling on the king side. Those are letter O, not zeros. |
| =Q | A pawn reached the last rank and became a queen. |
| Nbd2 | Either knight could reach d2, so the letter of the column it came from is added. |
Paste exactly what the page shows. If it says Qd5+, the password wants Qd5+: no 1. in front, no space in the middle, no full stop at the end. The copy button gives you the string with nothing added.
Why the answer usually ends in a plus, not a hashtag
The puzzles are all mate in two, and the fastest way to force a mate in two is to give check on the first move. That is why most answers end in +. The checkmate itself lands on the second move, and the second move is not part of the password.
So the hashtag is the one symbol you should not type. Qd5# is rejected where Qd5+ is accepted, because the game stores the first move of the pair and the first move is not the mate.
About one puzzle in ten opens with a quiet move instead, something like Ne7 or Kh6, which threatens mate without giving check. Those answers end in nothing at all. If this page shows a move with no symbol after the square, that is the answer, and you type it exactly like that.
Does the chess move break your other rules?
Rule 5, the digits have to add up to 25. Every square name carries a number, and it counts. Qd5+ adds 5. Nbd2+ adds 2. O-O adds nothing. The page prints the total under the answer so you can take that much out of the rest of your password.
Rules 7 and 9, the Roman numerals. The piece letters are K, Q, R, B, and N, and none of those is a Roman numeral. The capture symbol is a lowercase x, which does not count either. A chess move never changes your Roman numeral product.
Rules 12 and 18, the periodic table. A piece letter followed by a file letter can spell an element symbol. Nb, Ne, Nd, Na, Ba, Be, Bh, Ra, Rb, Re, Rf, and Rh all count. If your move is Nb5+, you have just added niobium, atomic number 41, and rule 18 will notice.
Rule 25, the sacrifice. Nine rules later the game makes you give up two letters for good. Do not pick a letter that is in your chess move. Sacrifice the Q after pasting Qd5+ and the password breaks on the spot.
If the game rejects the move
The move is almost always right and the board is almost always wrong. Work down this list.
- The side to move. This is the usual one. Check the line under the game's board and match it here.
- A piece one square off. Rebuild the sparse corner of the board rather than squinting at it.
- The board flipped. If the picture has Black at the bottom, flip this board before you place anything.
- A pawn on the first or last rank. That cannot happen in a real game, so the piece you placed is something else.
- Rarely, the puzzle has two moves that mate in two and the game only stores one. If everything else checks out, try the other checking move.
The short version: if this page did not say Mate in 2, the position on this page is not the position in the picture.
Need more than one move?
This page answers one question and gives one move. The chess best move calculator is the full tool: three candidate lines, an evaluation in pawns, and a reason in plain words for the move it picks.
It also takes a position the fast way, from a FEN, a PGN, or a public Chess.com or Lichess game link, so you never place a piece by hand.
How do I find the best move for the Password Game chess puzzle?
Copy the pieces from the game's picture onto the empty board on this page, set White or Black to move to match the line under the game's board, and press Find best move. Stockfish finds the mate in two and the page shows the first move, like Qd5+, ready to paste into your password.
Is the Password Game chess puzzle always mate in two?
Yes. Every puzzle in the set is a forced checkmate in two moves, and the password wants the first of those two moves. That is why this page tells you when the engine has found a mate in two: it is the proof that the board here matches the board in your picture.
Do I type the # for checkmate?
No. The first move is almost never the mate, so the stored answer almost never has a #. Across the 340 puzzles in the game's own files, 307 answers end in +, 33 end in nothing at all, and not one ends in #. Type what this page shows and nothing more.
Do I include the move number, like 1.Qd5+?
No. The answer is the move on its own, so Qd5+ and not 1.Qd5+. There is no move number, no space, and no full stop. The copy button on this page copies exactly the string the game expects.
Can I upload a screenshot of the board?
Not yet. Reading a board from a picture is planned, but it is not built. For now you place the pieces yourself, which takes about a minute for a puzzle with eight to twelve pieces. Tap a piece in the tray, then tap the squares it sits on.
What does "White to move" mean?
It is the game telling you which side plays next, and it decides the whole answer. The same pieces with White to move and with Black to move give different moves. The line sits under the game's board. Set the same option on this page before you press Find best move.
Is this free, and is my position uploaded?
It is free, with no account. Stockfish 18 runs inside this browser tab as WebAssembly, so the pieces you place never leave your device and there is no server doing the thinking. The privacy page has the detail.
What is algebraic chess notation?
It is the standard way of writing a chess move: a capital letter for the piece, then the square it moves to. The columns, called files, are lettered a to h across the board and the rows, called ranks, are numbered 1 to 8 up it, so Qd5 is the queen going to d5. A capture adds x, a check adds +, and a checkmate adds #.