What Is a Flow Puzzle? Flow Free vs the Pipes Game
A flow puzzle is a grid game where the goal is to build unbroken flows that connect or fill the board — and the name covers two related games: the connect-the-dots type (Flow Free, based on Numberlink), where you draw paths between matching endpoints, and the rotate-to-connect type (the pipes game), where you turn fixed tiles until a flow spreads through one connected network. You can play the rotate-to-connect flow puzzle free here.
Both share one idea — a complete, gap-free flow — but the way you play them is different. Here is how to tell them apart and which one you are looking for.
The two kinds of flow puzzle
"Flow puzzle" is used for two different games that share a single idea: making a complete, gap-free flow. Knowing which one a site means saves a lot of confusion.
Connect-the-dots flow (Flow Free, Numberlink)
In the connect-the-dots type you draw a path between each pair of matching coloured dots so the paths never cross and together fill every cell. Flow Free (2012) is the best-known app, and it descends from Numberlink, a pencil-and-paper puzzle popularised by Nikoli. The skill is routing every colour without trapping another.
Rotate-to-connect flow (the pipes game)
In the rotate-to-connect type you turn fixed pipe tiles until every pipe joins one connected network and the flow lights up outward from a central source. This is the Net / FreeNet pipes game — calm, no timer, with exactly one solution per board.
Flow puzzle types compared
The three games most often called a "flow puzzle" differ in what you actually do.
| Type | How it works | Your input | Examples |
|---|---|---|---|
| Connect-the-dots | Draw non-crossing paths linking matching endpoints to fill the grid | Drag / draw paths | Flow Free, Numberlink |
| Rotate-to-connect | Turn fixed tiles so all pipes form one flowing network | Rotate tiles | Pipes game, Net, FreeNet |
| Water flow | Route water through pipes to reach a target outlet | Rotate / place | Water pipe puzzles, plumber games |
Which flow puzzle are you looking for?
If you want to draw paths between coloured dots, you want the Flow Free / Numberlink type — a separate app. If you want to rotate tiles until everything connects and lights up, that is the pipe puzzle. The pipes game is the flow puzzle you can play right here, free and with no download.
How to solve a flow puzzle
Whatever the type, start from the moves that are forced and never leave a gap. The general method is the same:
- Start at the constraints — corners, edges and endpoints have the fewest options, so they resolve first.
- Keep the flow unbroken — extend one continuous path or network at a time rather than filling cells at random.
- Never strand a cell — avoid any move that cuts off a square or a connector with no way to join the flow.
- Plan the whole grid — a flow puzzle is solved only when every cell or pipe belongs to the finished flow.
For the rotate-to-connect version specifically, see our full guide to solving a pipe puzzle.
Play a flow puzzle now
Play the free rotate-to-connect flow puzzle in your browser — turn the pipes until the flow reaches every tile, from a gentle tutorial up to wrap-around boards and a new daily puzzle. Stuck on one? The Pipe Puzzle solver will flow it for you.
Frequently asked questions
Is a flow puzzle the same as Flow Free?
Flow Free (2012, Big Duck Games) is one popular flow puzzle — the connect-the-dots type, based on the Numberlink pencil puzzle. But "flow puzzle" is a broader term that also covers the rotate-to-connect pipes and water games, so the two are related but not identical.
Is a flow puzzle the same as a pipe puzzle?
Often, yes. The rotate-to-connect pipe puzzle is frequently called a flow puzzle because connected pipes carry a flow out from a central source. The connect-the-dots Flow Free type is a different mechanic that happens to share the name.
What is Numberlink?
Numberlink is the classic Japanese pencil-and-paper puzzle, popularised by Nikoli, in which you connect pairs of matching numbers with non-crossing paths that fill the whole grid. Flow Free is its digital descendant.
Are flow puzzles good for your brain?
Yes. Both the connect-the-dots and rotate-to-connect types train spatial reasoning and forward planning — you have to picture the whole network before committing, much like Sudoku or nonograms.
Where can you play a flow puzzle free online?
You can play the rotate-to-connect flow puzzle — the pipes game — free here in your browser, with no download. The connect-the-dots Flow Free is a separate mobile app.