How to play Tango — the free daily suns-and-moons logic game

Tango takes the small, satisfying deduction puzzle that has become a fixture of many people’s morning routine and keeps it deliberately simple. There is a new board every day, shared by everyone, so you can compare times with friends. When the daily puzzle is done, an unlimited practice mode generates fresh, uniquely-solvable grids whenever you want more.

Three things set the tone. First, it is free — there is no paywall and no premium upsell. Second, it asks for no account: your streak and statistics live in your own browser, so you can start the moment the page loads without handing over an email address. Third, the interface is quiet — a type-set board, a live tally of filled cells, time and conflicts, a plain-text share, and zero emoji anywhere in the experience.

It is also built to be read by everyone. The two symbols differ by shape, not colour — a rayed disc for the sun, a crescent for the moon — so nothing depends on colour alone, and locked clue cells carry a small gold corner pip as a second cue. The whole board renders before any script runs, so it works on a slow connection and is fully keyboard-operable.

Unlike a word game, Tango asks for no vocabulary at all: it is pure logic. Every board is generated with exactly one solution and checked by a constraint-and-backtracking solver before it is published, so you never have to guess — every cell can be reasoned out from the rules and the clues. Because there is no timer forcing your hand, the game rewards a careful read of each line over raw speed.

The day’s board is the same for every player, carries its own puzzle number, and rolls over at midnight in your own time zone. Solve it and your streak ticks up; come back tomorrow to keep it alive. When you finish, you can copy a tidy plain-text summary — your time and whether you took a hint, never the solution — and paste it to friends without spoiling their solve. A statistics panel keeps your games played, win rate, current and best streak, and fastest hint-free time, all stored only on your own device.

The goal is to fill every cell of a 6×6 grid with one of two symbols — a sun (a rayed disc) or a moon (a crescent). Tap an empty cell to cycle it empty → sun → moon → empty; the pre-filled clue cells never change. The finished grid has to satisfy three rules at once:

Balance every line. Each row and each column must hold exactly three suns and three moons. There are six cells in a line and no ties are allowed, so the split is always three and three.

No three in a row. The same symbol may never appear three times in a row horizontally or vertically. Two suns side by side are fine; a third touching sun is not. The same goes for moons.

Obey the signs. A small sign printed on a border sets the two cells it joins. An = means they must be the same; a × means they must be opposite. These are firm constraints, not hints, and they often unlock a chain of forced moves.

You do not start from a blank grid. A handful of cells arrive pre-filled as givens — each marked with a small gold corner pip, and locked so a tap can never change them — and it is those givens, together with the border signs, that anchor the whole deduction. From that scaffold, every other cell can be reasoned into place; the givens are simply the first facts you build on.

A few details are worth knowing. Every well-formed Tango has a single solution reachable by logic alone — you should never need to guess. As you play, the board rings any conflict in coral and outlines a broken sign, and a live status line tracks filled cells, elapsed time and conflicts. Stuck? A hint fills the next forced cell, and show solution reveals the whole grid.

The whole game is just these three rules pushing cells into place. Take a single row that already shows three symbols — a sun in the first cell and a pair of moons in the fourth and fifth — with the rest empty:

Cell 6 is forced. Cells four and five are both moons. If cell six were a moon too, that would be three moons in a row — forbidden. So cell six must be a sun.

Cell 3 is forced. Cells four and five are moons again. If cell three were a moon, cells three, four and five would be three moons in a row. So cell three must be a sun.

Cell 2 falls out by counting. The row now shows suns in cells one, three and six — that is three suns already. A row holds exactly three of each, so no cell can be a sun. The one empty cell, cell two, must be a moon.

The finished row reads sun, moon, sun, moon, moon, sun: three suns, three moons, and no run of three alike. Notice that we never guessed — each move was forced by a rule. That is Tango in miniature. A full board is the same reasoning applied across all six rows and six columns, with the = and × signs handing you extra footholds.

The signs work the same forcing way. If a cell holds a moon and an = joins it to its neighbour, that neighbour is a moon as well. If a × joins them instead, the neighbour must be a sun. Fill one side of a sign and the other side is settled at once:

LinkedIn popularised this suns-and-moons format, and we are happy to say so plainly: Tango on duplixo is the same kind of puzzle. What we have done is keep it free, make the practice unlimited and add a proper built-in solver. This is an independent clone with its own original code and its own generated boards — not a copy of anyone’s puzzles. The table below lays out the practical differences for the standard daily experience.

In practice the gap that matters most is what happens after you solve. With duplixo, finishing the daily board is not the end — an unlimited practice mode spins up fresh, uniquely-solvable grids so you can keep playing without any of it touching your daily streak. There is no “come back tomorrow” wall, and nothing to unlock with a subscription.