Pipe Flow

Every tile carries connections on its edges, and every tile has been spun. Rotate them until an unbroken path runs from the source in the top-left corner to the drain in the bottom-right — inside a turn budget that is always enough.

It runs entirely on your device: 0 network requests, works offline. No ads, no account, nothing to buy, and no betting, money or prizes of any kind.

1. Focus the board — click it, or press Tab until it is focused.
2. Move with the arrow keys. The cursor is outlined, not just tinted.
3. Rotate with Enter. The tile turns a quarter-turn clockwise.
4. Read the digit. Each tile shows how many edges it carries. A 2 is either a straight or a bend, and only one of those can turn a corner — so the digit tells you what a tile can do before you spend a turn finding out.
5. Connect the two ends before the turns run out. Two tiles join only when both carry the edge they share.

How do you solve a rotating pipe connection puzzle?

Work from the two fixed ends inwards rather than from the middle outwards. The source and the drain each have exactly one edge that leaves the board, so the tile next to each of them is forced — there is only one direction the path can arrive from. Fix those two, and each one forces its neighbour in turn. The digit on each tile does the rest of the work: a tile showing 2 is either a straight or a bend, so if the path has to turn there and the tile is a straight, the route does not run through that tile at all and you can stop considering it.

Is every board actually solvable?

Yes, by construction. A route is carved from source to drain first, and the tiles along it are given exactly the edges that route needs — so a winning arrangement exists before anything is spun. Every tile is then rotated a random amount, which cannot destroy a solution that is already there. The budget is the cost of turning that route back, plus a margin, so it is always enough to win.

Why does the turn budget exist at all?

Because without it the game is "rotate everything until it works", which is not a puzzle. The budget is derived from the generator's own route rather than picked by hand, so it is tight enough to make you read the board and generous enough to survive a wrong guess.

What are the tiles that are not on the route for?

They are decoys, and they are real pipes — if one happens to complete a connection for you, that counts as a win. The budget is priced on the intended route, so a lucky short cut only ever helps.

Does it work offline?

Yes. Once the page has loaded once, the whole game is on your device — rules, board, everything. There is no server involved in play at any point.

Is there any money, betting or in-app purchase in this?

None, and there never will be. No currency, nothing to buy, no lives to refill, no wager of any kind.

Can I play it with a keyboard or a screen reader?

Both. Arrows move, Enter rotates, and the board publishes a row-and-column description that names each tile's edges in words — "up and right" rather than a colour. The connections are drawn as shapes, so nothing depends on telling hues apart.

Four by four, sixteen tiles, and a budget of the carved route's cost plus four. The cost is computed per tile against its own symmetry, so a straight piece is priced at one turn rather than three.

Slide Fifteen is the other spatial puzzle here — it asks you to plan a route for a tile rather than a route for a connection.

Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.