How to play
Every move slides all the tiles as far as they can go in one direction. When two tiles with the same number collide, they merge into one tile with their sum: 2 + 2 becomes 4, 4 + 4 becomes 8, and so on. After each move a new 2 (or now and then a 4) appears in an empty square. Build a 2048 tile to win, then keep going for 4096 and beyond. The game ends when the board is full and no two neighbouring tiles match.
Controls and board sizes
Use the arrow keys or WASD on a keyboard, or swipe on the board on a phone. You can take back your last move once with Undo (or the Z key), which is handy after a slip of the finger. Play 4×4 for the classic game, or pick 5×5 or 6×6 for more room and longer runs. Each board size keeps its own best score and your game in progress, so you can close the page and carry on later. The leaderboard uses the classic 4×4 board.
Tips
Pick a corner and keep your biggest tile in it. Most strong players use only two or three directions, so the big tiles stay lined up along one edge in descending order. Save the fourth direction for emergencies, since it pulls your biggest tile out of its corner, and merge small tiles early so the board does not clog up.