Just Masyu
Draw one loop through every pearl. It runs straight through a white pearl and turns beside it; it turns on a black pearl and runs straight on both sides.
Today's board
One board a day, the same one as in the app.
A new board
The pearl rules and the three cell rules, nothing else.
The rules
- Draw one closed loop through the centres of the cells. It never forks or crosses itself.
- The loop passes through every pearl.
- Through a white pearl it runs straight, and it turns in at least one of the cells just before and after.
- On a black pearl it turns, and it runs straight through the next cell on both sides.
Tap between two cells to draw a link, again to cross it out, and once more to clear it. Drag from cell to cell to draw a run of loop; a drag that starts on loop rubs it out. With a keyboard: arrow keys move, Shift and an arrow change the link that way.
The techniques
The solver that builds each board knows 13 named techniques, listed here in the order it reaches for them. A board is kept only if they are enough to finish it.
- Straight Through
- Two Links Out
- No Room That Way
- Bend Beside White
- Blind Cell
- Only Way On
- Full Cell
- Black Neighbours
- Three in a Row
- Early Ring
- Test a Pearl
- Two Sides
- Test a Link
Questions
Do I ever have to guess in Masyu?
No. Every board is proved to have exactly one solution before it reaches you, and each step can be reasoned out.
Is Masyu free to play here?
Yes. Today's board and new 6×6 and 8×8 boards at every difficulty are free, with no account and no ads. The 10×10 boards, the lessons and the hints come with Just Masyu, the app, which is on its way to the App Store.
Is today's board the same as in the app?
Yes. The daily board is made from the date, so this site and the app serve the same one.
Along the street
In the app
Just Masyu is on its way to the App Store: thirteen named techniques, each with its own lesson, hints that explain their argument on your board, and 10×10 boards.