Sun & Moon Signs
balance every line · = same · × different

Play Sun & Moon — Binary Puzzle with Signs

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Tap: ☀ → ☾ → emptyS / M tools, drag to fillRight-click cycles back

How to play Sun & Moon

Sun & Moon is a binary puzzle — the same family as Binary (Takuzu) — with an extra kind of clue: small signs between neighbouring squares.

An = sign says the two squares hold the same symbol. A × sign says they are different. Together with the classic rules — equal suns and moons in every line, never three alike in a row — they lead to exactly one answer.

Choose Signs only for puzzles with a single starting symbol, or turn on the classic ‘no twin lines’ rule for an extra challenge. If you enjoy daily sun-and-moon style puzzles, the rules here are the same.

How to play Sun & Moon

Fill the grid with suns and moons: the same number of each in every row and column, never three alike in a row, and every = or × sign obeyed.

The rules

  1. Every square holds a sun or a moon.
  2. Each row and each column has as many suns as moons.
  3. No more than two of the same symbol may sit next to each other in a row or column.
  4. Squares joined by = hold the same symbol; squares joined by × hold different symbols.
  5. Optional classic rule: no two rows, and no two columns, are identical.

Playing here

  1. Choose the rules, how many clues are signs, a size and a difficulty, then press New Puzzle.
  2. Tap a square to cycle sun → moon → empty, or pick the Sun or Moon tool (S / M) and drag across squares.
  3. Broken rules light up red: three in a row, too many of one kind, or a sign that doesn’t fit.
  4. Hint explains the next square — signs, pairs, sandwiches, full lines and more.

Tips

The full guide, with a worked example and common mistakes: How to play Sun & Moon.

Questions

Is this the same as the daily sun-and-moon puzzles?

It follows the same rules as the popular daily versions: suns and moons, balanced lines, no three in a row, and = / × signs.

Can I play with 0 and 1?

Yes — turn on ‘Show 0 and 1 instead of ☀ and ☾’ under New Puzzle.

Is there always one answer?

Yes — every puzzle here is checked to have exactly one solution.

How do I solve one I found elsewhere?

Open the Sun & Moon Solver, enter the symbols and signs, and press Solve.

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