Pipes

How to play Pipes

The goal

Turn the tiles so that every pipe joins one network, fed by the pump in the middle, with no opening left pointing at nothing. When it is done, the liquid fills every pipe and the clock stops.

The rules

1. Tiles only turn. Tap a tile to turn it a quarter clockwise. Pieces never move to another square.
2. Four kinds of piece. An end opens one way, a straight two opposite ways, a bend two neighbouring ways, and a tee three ways. There are no crossings.
3. Every opening must meet another. An opening has to face an opening on the next tile. In Classic, an opening that faces the board’s edge is a leak.
4. Everything joins the pump. The pump sits on the middle tile. Pipes joined to it fill with liquid as you play, so you can see what is connected.
5. Any leak-free answer counts. If every tile is joined and nothing leaks, the board is solved, even if your answer differs from ours. A solved network never has a loop.

Modes

• Classic: the edges are walls. Boards from 4×4 to 12×12.
• Wrap: the edges join. An opening on the right edge meets the tile at the left end of the same row, and the top meets the bottom. Boards from 4×4 to 12×12.
• Flow: the liquid moves by itself. After a short grace period it leaves the pump and takes one step at a time along joined pipes, branching at tees. Once it fills a tile, that tile can no longer turn. If it reaches an opening that does not meet another (or a wall), it leaks and the game is over. If it fills a closed-off stretch of pipe that can’t reach the rest of the board, it is sealed in, and that ends the game too. Solve the board first, or fill every tile without a leak, to win. Boards from 4×4 to 8×8, with Walls or Wrap edges and Gentle, Steady or Quick liquid. A red warning marks a pipe the liquid is about to spill from.
• Today’s puzzle: one 6×6 Classic board a day, the same for everyone. Your score is your time. One attempt counts: if you start another game before solving it, it counts as unsolved. Restarting it puts the tiles back but keeps the clock running. If you leave and come back, the board stays covered until you carry on, and the clock waits with it.

Controls

• Tap or click a tile to turn it clockwise.
• Right-click turns it anticlockwise.
• Long-press a tile to lock it, so it cannot turn by accident. Long-press again to unlock.
• Turn, Turn back and Lock under the board choose what a tap does, so nothing needs a long press or a right-click.
• Undo takes back turns and locks (not in Flow: the liquid does not go back).

Keyboard

Tab to the board, then use the arrow keys to move (on Wrap boards they wrap around the edges). Enter or Space turns the focused tile clockwise; Shift+Enter or Q turns it anticlockwise. L locks or unlocks it, and U or Ctrl+Z undoes.

Tips

• Start at the edges and corners in Classic. A straight on an edge has only one way to lie, and an end in a corner has only two.
• Two ends never face each other unless the board is just those two tiles: they would close off a network with nothing else joined.
• Lock tiles you are sure of. It costs no time and saves stray taps.
• In Flow, use the grace period to sort out the tiles around the pump, then keep working just ahead of the liquid.

Questions

Is every board solvable? Yes. Every board is made by building a working network and then turning its tiles at random.

Do I need an account? No. Your game saves on this device automatically. An optional account adds cloud saves across devices.