Board Coverage: Chess Attack Map

See which squares each side controls on chess.com, who wins contested squares, and which pieces are hanging. Built for study.

See the whole board at a glance. Board Coverage colours every square on the chess.com board by who controls it, so you can spot weak squares, fights and loose pieces while you study. WHAT IT SHOWS • Coverage: blue squares are yours, red are your opponent's. The deeper the colour, the more pieces cover the square, including pieces lined up behind each other (a rook behind a rook, a queen behind a bishop). • Contested squares: squares both sides attack are split between the two colours. Whoever wins the exchange there gets the bigger share. • Hanging pieces: pieces that would lose material are outlined, with how many points are at stake. • One piece at a time: click any piece to see only its reach. Safe squares, risky squares, captures that win (+9) or lose (-2) material, the pieces it defends, and the lines it x-rays through for pins and skewers. HOW TO USE IT Open the analysis board, a puzzle or a game against the computer. A small bar in the bottom left switches between Coverage, Contested, Hanging and Off (Alt+C cycles through them). Click the extension's toolbar icon to turn the overlay on or off. BUILT FOR STUDY Board Coverage turns itself off on pages where you play other people (live and daily games, tournaments, puzzle battle), so it can't be used as outside help in a real game. To study one of your own games, open it in Analysis. GOOD TO KNOW • Who wins a square is worked out by playing out the captures on it, each side using its cheapest piece first. It's a quick static picture to train your eye, not an engine: pins and checks during a trade aren't taken into account. • Collects no data. Your chosen view is saved in your browser and nothing is sent anywhere. Board Coverage is an independent project and is not affiliated with or endorsed by Chess.com.