numberlink · 5 min read

How to Play Numberlink

Trace non-crossing paths to unite matching pairs across the grid.

Numberlink is a path-drawing puzzle. The grid contains pairs of identical numbers. Your job is to draw a path between each matching pair, with paths going only horizontally and vertically, never crossing each other, and (in our standard variant) covering every cell in the grid.

The Puzzle

A 5×5 puzzle with six numbered pairs. Each circled number is a clue. Paths must connect each number to its twin.

Starting puzzle: 12 clues forming 6 pairs. Connect each pair so all paths together cover every cell.

The Three Rules

Rule 1: Each pair of matching numbers must be connected by a path

Paths run only orthogonally (up/down/left/right — no diagonals) and consist of unit-length segments through cells.

Rule 2: Paths cannot share or cross cells

No cell may belong to two paths. No path may cross another. Each cell on the board ends up labeled with exactly one number (the number of the path passing through it).

Rule 3: Every cell is on some path (in the standard variant)

Numberlink is sometimes played without this rule — but most published puzzles (including ours) require full coverage. No empty cells in the finished puzzle.

Walkthrough

Step 1 — The corner 1 has only one way to leave

The clue 1 at row 1, column 1 sits in the top-left corner. Two cells are reachable: right (row 1, column 2) or down (row 2, column 1).

Down is blocked — row 2 column 1 holds clue 3. Path 1 cannot enter another clue cell, so the only option is right. And the matching 1 is on row 2 column 5, so path 1 will need to head all the way across the top row and down the right side.

Path 1 goes from the corner across the top row, then down to its twin at row 2 column 5.

Step 2 — The 3 at row 2 column 1 has limited exits

Clue 3 at row 2 column 1 has neighbors: up (clue 1), right (clue 2), down (no clue). Up and right are blocked by clue cells, so path 3 starts going down to row 3 column 1.

From (3, 1), the path turns right and reaches the matching 3 at (3, 2).

Path 3 goes down then right, just two steps.

Step 3 — The remaining paths fill the lower half

The 2 at (2, 2) and (2, 4) connects through (2, 3). The 4 at (3, 3) and (4, 5) needs a path that wraps around. The 5 at (4, 4) and (5, 1) traces a Z-shape across rows 4 and 5. The 6 at (5, 2) and (5, 5) runs along row 5.

The unique solution:

Solved! Six paths thread through every cell, no crossings.

Tips for Beginners

Start with corners and edges. A clue in a corner has at most 2 exits. A clue on an edge has at most 3. Often only one is available.
Identify forced first moves. A clue surrounded by other clues on three sides has only one valid first step.
Trace short pairs first. If two matching numbers are nearly adjacent, the path between them is short and constrained.
Watch for cell coverage. If you reach a state where some cells can't be reached by any remaining path, an earlier choice was wrong. Backtrack.
Don't overlap. Two paths through the same cell is the most common beginner mistake. Once a cell has a number, another path can't use it.

Ready to try one yourself? Hit the button below to play your first Numberlink.

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