Masyu FAQ

Masyu is a Japanese logic puzzle published by Nikoli. On a grid containing white and black circles (pearls), you draw a single closed loop through cell centres that passes through every pearl. The loop turns on black pearls and goes straight on both sides of them; it goes straight through white pearls and turns in at least one adjacent cell.

It is pronounced “MAH-shoo” (ましゅ, mashu). The spelling with “sy” comes from the Kunrei-shiki romanisation of Japanese.

1) Draw one closed loop through cell centres using horizontal and vertical segments, with no branches or crossings. 2) The loop must pass through every pearl. 3) On a black pearl the loop turns 90° and travels straight through the next cell on both sides. 4) On a white pearl the loop goes straight and must turn in the cell before or after it (or both). See How to play Masyu for diagrams.

No. The loop must visit every pearl, but empty cells can be skipped. This is one of the main differences between Masyu and puzzles such as Yajilin.

Black pearls are corners: the loop must turn on them and then continue straight for at least one more cell in both directions. White pearls are straights: the loop goes straight through them and turns in a neighbouring cell.

No. Both arms of a black pearl pass straight through the adjacent cell, so the earliest the loop can turn again is two cells away from the pearl.

Yes. The rule requires a turn on at least one side; turning on both sides is allowed.

A properly constructed Masyu has exactly one solution. Every puzzle on MasyuPuzzles.com is verified by our solver to have a unique solution reachable through logical deduction.

Masyu is easy to learn but can be very challenging. A 6×6 Easy takes most people a few minutes, while a 25×25 Hard can take more than an hour. Difficulty depends on grid size, the number of pearls and how deep the required logic is.

Easy and Medium puzzles can be solved with direct deductions — the pearl patterns and loop rules — with Easy puzzles providing extra pearls. Hard puzzles have fewer pearls and require short “what-if” contradiction chains. None require guessing.

Start with 6×6 Easy, read the illustrated rules, then learn the first eight techniques in our strategy guide. Move up a size once Hard feels comfortable.

Begin at the border (corner and edge pearls), look for pearl groups such as adjacent black pearls and rows of three white pearls, mark impossible edges with ✕, extend forced line ends, avoid closing small loops and use parity in sparse areas. Our strategy guide explains 15 techniques.

No. Look for an edge you can rule out, re-check every white pearl for a forced turn, or try a short what-if: assume a line and see if it leads to a contradiction. If it does, the opposite is proven.

Logic puzzles like Masyu exercise planning, spatial reasoning, working memory and pattern recognition. They’re a fun way to keep your mind active, though no puzzle is a substitute for medical advice.

Yes. With no numbers or words, Masyu is great for children who can follow simple rules — 6×6 Easy puzzles are ideal, and the printable sheets work well in classrooms.

Yes. All puzzles, the daily/weekly/monthly challenges, the solver and printable sheets are free with no account required.

Yes. Lines, timers and hints are saved automatically in your browser’s local storage. Statistics, best times and daily streaks are stored on your device too.

Drag your finger across cells to draw lines; drag back to erase. Tap an edge to cycle between line, ✕ and empty, or turn on ✕ mode in the toolbar.

Hint first removes a line or ✕ that doesn’t belong to the solution; if everything is correct, it adds a correct segment next to your existing lines. Check flashes any mistakes in red without changing anything.

The Daily Masyu changes at midnight in your local time zone. The Weekly Masyu changes each Monday and the Monthly Masyu on the first of each month.

Yes. Use the Print button on any puzzle, or the printable Masyu generator to create worksheets with answer keys.

Yes. Our Masyu solver lets you place pearls on any grid size, then shows the solution and tells you whether it is unique.

Masyu was developed and published by the Japanese puzzle company Nikoli in its magazine Puzzle Communication Nikoli, first as a white-circle-only puzzle called Shinju no Kubikazari (“pearl necklace”).

The name comes from a misreading of 真珠 (shinju, “pearl”) that became an in-joke at Nikoli. The often-repeated translation “evil influence” comes from an unrelated word, 魔手, with the same pronunciation.

Yes. “Pearl”, “pearl puzzle” and “Masyu” all refer to the same genre. Some apps also call it “Mashu”.