How to play Zip
Zip is a path puzzle on a six by six grid. Some squares carry a number, and some edges are walled off. You draw a single line, and four rules decide where it can go:
- Start on 1 and finish on the highest number.
- Reach the numbers in order, 1 then 2 then 3, and so on.
- Cover every square exactly once. No square is left out, and none is used twice.
- Never cross a wall, and only move up, down, left or right.
Drag across the squares to draw, or tap them one at a time. Tapping a square already on your line cuts back to it, so you can unpick a wrong turn without starting again. The arrow keys work too, and Backspace steps back one square.
Tips for beginners
- Count the squares, not just the numbers. The line has to fill all 36, so a route that strands even one empty square in a corner is wrong however neat it looks.
- Corners and dead ends first. A square with only two open edges has its route forced: the line must come in one side and leave the other.
- Walls are gifts. Every wall removes a choice. Work outwards from the most walled off part of the grid.
- Never split the board. If your line cuts the empty squares into two separate pockets, you cannot reach both, so back up.
- Never guess. Every board here has exactly one path. If you are stuck, there is a square whose route is already decided.
Where Zip comes from
Zip asks for one unbroken line that visits every square exactly once, a question mathematicians have been asking for more than 150 years.
- 1857 The Icosian game William Rowan Hamilton sells a puzzle asking for a route that visits every corner of a dodecahedron exactly once.
- 2008 Hidato Israeli mathematician Gyora Benedek publishes Hidato: a grid filled with a chain of numbers, each one touching the next.
- Today Zip You draw the chain yourself. The numbers are checkpoints to pass in order, and walls block the shortcuts.
- Also known as
- Hamiltonian path, number path
- Puzzle family
- Route logic
- Our board
- 6 by 6, numbers and walls
- What it trains
- Planning ahead
Did you know? A route that visits every point exactly once is still called a Hamiltonian path, after Hamilton. Benedek has said Hidato came to him while scuba diving in the Red Sea.
Is this the same as LinkedIn's puzzle?
No. This is our own Zip, in the same one line style. Every board is generated here and checked by a solver to have exactly one path, so the answers will not match any official daily answer. It is free, needs no account, and your streak is saved in your own browser.