Chess Vision Overlay

Reads the chess board on screen and draws faint lines showing every legal move for you and your opponent, plus hanging-piece alerts.

See every legal move on the board at a glance. Chess Vision Overlay reads the chess board on your screen and draws faint lines over it, so you can spot threats, captures and hanging pieces while you learn. WHAT YOU SEE • Blue lines: every legal move for your pieces. A dot marks a quiet move, a ring marks a capture, a dashed line marks castling. • Red lines: every move your opponent could play right now. • Rings around pieces: red means your piece is hanging (attacked and undefended), orange means attacked but defended, green means an opponent piece you can take for free. • Hover over any piece to spotlight only its moves. Colours, line opacity and which side to show are all adjustable from the popup. WORKS ON ANY 2D BOARD On chess.com and lichess the overlay activates automatically and reads the exact position from the page, with no setup. On any other site it works visually: it screenshots the tab, splits the board into 64 squares and recognises the pieces. That means it works on chesstempo, YouTube videos, puzzle sites, PDFs of games, or anywhere a flat 2D board is on screen. Calibrate once per site by showing the starting position and clicking "Calibrate from starting position". If the board isn't found automatically, drag a box over it with "Select board region". MADE FOR LEARNING This is a visualisation aid, not an engine. It shows what is legal and what is under attack, and never suggests a move. Use it to train your board vision, review games, or follow along with videos. Please respect the fair-play rules of any site where you play rated games. PRIVACY Everything runs locally in your browser. Screenshots are processed on your machine and never leave it. No accounts, no tracking, no data sent anywhere. KNOWN LIMITS • Visual mode needs a plain 2D board. 3D boards and heavily animated piece sets may be misread. • En passant is not shown. Castling is shown whenever the king and rook are on their home squares with a clear path. • In visual mode the overlay refreshes about a second after a move. On chess.com and lichess it updates instantly. Open source: https://github.com/bhattji007/chess-vision-overlay