Vitaly.German

· 4 min read · updated

Can you beat a chess robot?

A chess game in two flavors: a native C++/Qt desktop app, and a browser version against Stockfish you can play right on this site.

This project comes in two flavors: a native desktop app written in C++ with Qt, and a JavaScript version you can play instantly, right here on the site.

Play it in your browser

A chess board built from plain HTML, CSS and SVG, playable against Stockfish compiled to WebAssembly and running entirely in your browser. There are no server round-trips for moves.

  • A main menu: play the robot at a level from 0 to 20 as White, Black or a random color, or play a friend on the same device. Online play with a link or QR code is coming.
  • Drag the pieces or tap to move. They slide across the board instead of teleporting, and legal moves show up as dots.
  • Move history in official algebraic notation (with little piece icons, or plain letters), or in the old from–to style.
  • Copy the game as PGN to analyze it anywhere, plus undo, surrender, flip the board, board colors, two piece sets and optional sound effects.
  • Built for phones too: the board fills the screen in portrait, and the controls move beside it in landscape.

The chess menu: a row of pieces above the title "Can you beat a chess robot?", and three cards: Play vs Robot with a level slider and a White, Random or Black choice, 2 Players on this device, and Play a friend online marked "Coming soon"

Here’s a game against the robot in dark mode. The white bishop is picked up, and the dots show where it can go; the ring around the black knight on d5 means it can be captured. Each side’s captured pieces sit next to the player names, and the move list on the right keeps score in figurine notation. If things go badly, there’s always Undo. Or, for the truly desperate, Surrender. The robot is a gracious winner.

A game against Stockfish in dark mode: the board with a selected white bishop and dots on its legal squares, the move list on the right in figurine notation, and the Undo, Flip, Copy PGN, Surrender and New game buttons

Two players, one screen

No robot needed: pick “2 Players” and the same board becomes a pass-and-play game for two people sharing one device. In “Face to face” mode Black’s pieces and name are drawn upside down for the player sitting across the table. Lay a phone or tablet flat between you, and it’s just like a real board, minus hunting for that missing pawn under the sofa. Prefer to pass the device back and forth? “Flip each move” turns the board for whoever’s turn it is.

A 2-player game on a phone in face-to-face mode: Black's pieces and name are upside down at the top, White's at the bottom, with a one-line move list and the action buttons below the board

The first browser version

The first web version drew everything on a canvas, with Unicode chess symbols for pieces and a difficulty number box under the board. It worked, but it was click-only and a bit cramped on phones, which is what the 2.0 redesign set out to fix.

The first browser version in dark mode: a canvas board with captured pieces above and below it, a History panel listing 14 moves, and the Difficulty, Play against the robot, Undo and Surrender controls

The original C++/Qt version

The project started life as a native Qt chess UI written in C++, before being ported to the browser. See the C++ code on GitHub.

Gameplay demo of the desktop app. Watch on YouTube

Where it all started

For comparison, here’s an early video of one of the first working versions of the desktop app:

“Chess++ program gameplay”, the early version. Watch on YouTube

Play chess now →