2048

The rules, in full

The board is a 4 by 4 grid, and a game starts with two tiles on it. Every move slides all the tiles as far as they will go in one direction: up, down, left or right.

• Two equal tiles that meet merge into one, worth their sum: two 2s make a 4, two 64s make a 128.
• A tile merges only once per move. A row of 4, 4 and 8 slid left becomes 8 and 8, not 16.
• The pair nearest the wall you are sliding towards merges first. Three 2s slid left leave a 4 on the left and a 2 beside it; slid right, the 4 ends up on the right.
• After every move a new tile appears on a random empty square. Nine times in ten it is a 2, otherwise a 4.
• A move that changes nothing does not count. No tile appears, and you cannot use it to pass.
• The game ends when no move can change the board: every square is full and no two neighbours match.

Scoring

Every merge adds the value of the tile it creates. Making a 4 is worth 4 points, making a 256 is worth 256, and making the 2048 tile is worth 2048. Sliding without merging scores nothing. Your best score is saved in the browser and shown beside the current one.

Reaching 2048, and going past it

When you build a 2048 tile, the game says so. Tap to dismiss the message, or simply make your next move: the board stays as it is, tiles keep doubling to 4096 and beyond, and the score keeps growing until you run out of moves. There is no undo, so every move is final. The New button starts again at any time.

Strategy that actually helps

Pick a corner and keep your largest tile in it. A big tile in the middle of the board splits it in two and blocks merges on every side. In a corner it only has two neighbours to worry about.

Keep the row along that corner full. If your big tile sits bottom left, keep the bottom row packed, so that sliding left or right never pulls the big tile out of place. A gap in that row is how a 2 ends up in the corner.

Use three directions, and keep the fourth for emergencies. With the corner at the bottom, down, left and right hold the shape. Sliding up lets a new tile drop in under your big one, and it can take many moves to undo that damage.

Build a descending chain. Line the tiles up from the corner in falling order, 512 then 256 then 128, so that one new merge at the small end can run all the way up the chain.

Count empty squares, not points. A move that merges two small tiles and leaves three squares free is usually better than a larger merge that leaves one. Most games are lost to a full board, not to a lack of big tiles.

Watch which pair merges. Because the pair nearest the wall goes first, sliding the same row left or right can leave the leftover tile on different sides. Choose the direction that keeps the leftover away from your corner.

A little history

2048 was released in March 2014 by Gabriele Cirulli, a young Italian web developer, who is usually said to have written it over a weekend. It was inspired by sliding-number puzzle games that had appeared shortly before, and Cirulli published its code as open source, which is why so many versions of it followed within weeks.

Common questions

Is it free? Yes. It runs in your browser, with no signup and nothing to download.

Does it work on a phone? Yes. Swipe in any of the four directions; a short flick is enough, and a diagonal counts as whichever direction it leans towards most. It works in portrait and landscape.

Is there an undo? No. Every move is final, which is why looking at empty squares before you slide matters.

Can I install it? Yes. Bananai can be installed as an app from the browser, and a game you have already opened usually keeps working when the connection drops.