How to solve hashiwokakero
Hashiwokakero — also known as bridges, or simply hashi — joins islands with straight bridges until every island carries exactly its number, nothing crosses, and the whole map hangs together as one group.
Most of the game is counting, and the counting comes in a few recognisable shapes. This page walks through them, simplest first, each on a small board you can step through at your own pace.
How to play
Join the islands with bridges until each island has exactly as many as its number says.
Bridges run straight — across or down — never cross, and at most two can join the same pair of islands.
In the end every island must hang together in one connected group.
Tap between two islands to bridge them, or drag out from an island. Repeat for a double, once more to clear.
The number is a promise about bridges, not neighbours — an island of 4 might spread four bridges across three directions or stack them in two. And the connectivity rule is not a formality for the end: it forbids moves all through the game, which is what the last technique below is about.
Full counts
Some islands ask for every bridge their position can carry: a 4 in a corner, a 6 on an edge, an 8 anywhere. Their bridges are forced before anything else is known — the first pencil strokes on any board.
One short of full
An island one short of its maximum cannot fill every direction — but it cannot skip one either. At least one bridge goes each way, and that is often enough to open a board up.
The isolation rule
The finished map must hang together as one group, and that forbids moves long before the finish: a bridge that would complete a small cluster and cut it off from the rest can never be right.
No timer. Leave and come back — it’s saved.
Play today’s bridges