Bopbun Path Puzzle: Rules and a Worked Solution

Learn the path puzzle controls, cover every open square, and follow a complete eight-square example with seven moves.

By Bopbun · November 2, 2026 · About 4 min read

Start at S and extend the line through neighboring open squares. Visit each open square once, leaving F for the final move. Use Undo when a route goes wrong; reaching the finish early will not complete the board.

This guide covers Bopbun's four-by-four path puzzle and its eight boards. Each board has a start, a finish and some open squares. The main worked example uses Level 2, where the top two rows are open. A later example shows how to undo a dead end on Level 3.

Two 4-by-4 boards show Bopbun's path puzzle, level 2. The upper two rows are open. Start at row 1 column 1, cross the first row, then return along row 2 to the finish at row 2 column 1; eight squares are covered in seven moves. — Original illustration of one checked level-2 path. Rows and columns start at 1. The start is already selected, so this path covers eight squares in seven moves. View full size

What counts as a valid move?

The start square, marked S, is already selected. Extend the current end of the line by one square up, down, left or right. Diagonal moves, blocked squares and squares already in the path cannot extend it. Moving across the edge of a row does not connect to the next row.

The Squares covered counter includes the start. A board is complete when the line visits every open square and ends at F. You can pause to inspect the board; there is no countdown.

Tap, drag or use the keyboard

Tap or click an unused square next to the current end. Continue one adjoining square at a time.
To draw continuously, press the current end and drag through adjoining open squares. Release to stop drawing. Skipping across a gap does not fill the missing squares.
While drawing an unfinished path, drag back to the immediately previous square to remove the last step. Repeatedly tapping a visited square does not undo it.
For keyboard play, use Tab to focus the board, then the arrow keys to move focus. Enter or Space chooses the focused square. Moving focus alone does not draw; the chosen square must still adjoin the line.

Correct a route without losing the board

Undo removes the most recent step and keeps the earlier path. It becomes unavailable when only S remains. Restart clears the path back to S on the same board.

After finishing a board, use Undo to reopen the last step if you want to change the route. Dragging on a completed board does not reopen it.

Level 2: eight squares, seven moves

Count rows from the top and columns from the left, starting at 1. S is at row 1, column 1; F is directly below it at row 2, column 1. Only the top two rows are open. This route applies to that board.

The starting counter is 1 / 8. Leave S selected and make these seven moves:

Move right to row 1, column 2.
Move right to row 1, column 3.
Move right to row 1, column 4.
Move down to row 2, column 4.
Move left to row 2, column 3.
Move left to row 2, column 2.
Move left to F at row 2, column 1.

The counter now reads 8 / 8 and the level is complete. The route travels along the top row, turns down at the right edge and returns along the second row.

Why the direct move to F is rejected

On Level 2, moving straight down from S to F would leave six open squares untouched. The game rejects that move and keeps the counter at 1 / 8. The message says, "Cover every open square before the finish." Follow the longer route around the two rows, arriving at F last.

Level 3: back out of a dead end

On Level 3, try moving down, right, then up from S. The counter reaches 4 / 10. Both open neighbors of your current square are already in the line, so there is no valid next move. The game keeps your route and shows, "No moves from here. Use Undo or Restart."

Choose Undo three times to return to S. The counter returns to 1 / 10.
From S, move right, down, left, down, right, right, up, right, and down to F.

This route covers all ten squares in nine moves. The start counts toward coverage.

Choose another board and know what resets

The Puzzle menu lets you choose any of the eight levels. Changing to another level starts it fresh. Next level becomes available after a completed board; on the last board, First level returns to Level 1.

Current progress is not saved or synced to an account. Refreshing the page returns to Level 1 with only its start selected. Switching away through the Puzzle menu also discards the current route. Finish your attempt before refreshing if you want to keep working on it.