Pipes

How to play Pipes (rotate & connect logic puzzle)

Pipes — sometimes called Net or Plumber — is a rotation logic puzzle. Every tile in the grid holds a piece of pipe that is stuck in place but free to spin: tap a tile and it turns 90 degrees clockwise. Your job is to rotate every tile until the whole network forms a single connected system running out from the water source in the centre of the board, with every last drop of water able to reach every tile and nothing leaking off the edge. Every puzzle here is generated and checked by a solver before you ever see it, so there is always exactly one way to finish the grid — you can always reason your way to the answer instead of guessing.

The goal

Rotate every tile so that the pipes line up end to end across the whole grid. When you are done, every tile must be connected back to the water source and there must be no open pipe end anywhere on the board — no connector pointing off the edge of the grid, and no connector pointing at a neighbour whose own connector does not point back. You are timed, and rotating a tile out of its correct final orientation counts as a mistake, so a clean, efficient solve scores best.

The grid and the water source

The board is a square grid — 5×5, 7×7 or 9×9 depending on the difficulty you choose. One tile near the centre of the grid is the water source, marked with a small droplet icon. Every other tile holds a fixed pipe shape that was carved out when the puzzle was built, but its rotation has been scrambled, so the piece you see at the start is very unlikely to already be facing the right way. As you rotate tiles into their correct orientation, the connected part of the network lights up in blue (green once it reaches the source's own tile), so you always have a live, visual read on how much of the network is actually plumbed through — not just visually lined up.

The pipe pieces

Every tile is one of four shapes, built from up to three connectors out of the four compass directions (north, east, south, west). An end piece has a single connector and simply terminates a branch. A straight piece has two connectors on opposite sides and passes water straight through. An elbow piece has two connectors on adjacent sides and turns a corner. A tee piece has three connectors and splits the flow in three directions. Tiles with four connectors (a full cross) never appear in a generated Pipes puzzle by design — a four-way piece looks identical in every rotation, so it could never be placed incorrectly, which would make that tile pointless to rotate. Capping every tile at three connectors keeps every single tile on the board a real decision.

Rules

• Tapping a tile rotates it 90° clockwise; four taps return it to where it started.
• A connector is only a real connection when both tiles agree — your tile must open toward its neighbour AND that neighbour must open back toward you. A connector pointing at a neighbour that is not open back is a dangling open end, not a connection.
• A connector may never point off the edge of the grid. Any tile with a connector aimed at the boundary is not yet correctly placed.
• The puzzle is solved only when every tile in the grid is reachable from the water source through a chain of mutual connections, and there is not a single open end anywhere on the board.
• Every generated puzzle has exactly one rotation for every tile that satisfies all of the above — there is always a unique correct solution.

Solving techniques

• Start at the source. Rotate the water source tile and its immediate neighbours first — everything you build must eventually connect back through them, so getting the centre right anchors the rest of the grid.
• Work the edges and corners. A tile sitting against the border of the grid can never have a connector facing outward, which usually narrows an edge tile down to only one or two sensible rotations immediately.
• Follow the dangling ends. When you rotate a tile so that a new connector opens toward an unrotated neighbour, watch that neighbour — it now has a strong hint about which way it needs to face to accept the connection rather than leave it dangling.
• Use the live highlight. The glowing, connected part of the network is your proof of progress: if a tile you just rotated does not light up, either it or one of its neighbours is still misaligned somewhere along the chain back to the source.
• Save tee pieces for last on a branch. A tee splits the flow three ways, so it is usually easier to first work out the two simpler arms around it and let the tee's correct orientation fall out from what its neighbours already demand.

Controls

Tap or click any tile to rotate it 90° clockwise; keep tapping to cycle through all of its possible orientations. There is no separate mark or undo action — every tap commits a rotation, and the live connectivity highlight shows you instantly whether that rotation helped. Use New Puzzle at any time to generate a brand-new grid at your current difficulty, use Daily to load today's shared puzzle, and use the size selector to switch between the 5×5, 7×7 and 9×9 boards.

Daily puzzle

The Daily button loads a special puzzle that is generated from today's date, so every player who taps Daily on the same UTC calendar day gets the exact same grid to solve — a fair way to compare times and scores with friends. The daily puzzle changes automatically at midnight UTC and is independent of the freely-repeatable New Puzzle grids, which use a fresh random seed every time you press the button.

Scoring and the leaderboard

Your score is calculated the moment the network is fully connected with no open ends: score = 10000 − seconds × 5 − mistakes × 200. A fast, mistake-free solve scores closest to the maximum of 10000; every second on the clock costs 5 points, and every mistake — rotating a tile away from its correct orientation after it had been sitting correctly — costs 200 points. The result is clamped between 1 and 99,999 and recorded separately for each difficulty, so each grid size keeps its own leaderboard.

Frequently asked questions