Binary puzzle (Takuzu): today's grid
Today's puzzle
Loading ยท the grid and its level
(a small spoiler)
Checked: exactly one solution, reachable by logic. The level is the hardest technique our solver needed, not the grid size.
Settings
Rule breaks (three in a row) always show in red. "Show mistakes" also marks cells that disagree with the solution.
Fill every cell with a white or a black circle. No row or column may have three of the same colour in a row, each row and column is half white and half black, and no two rows (or two columns) may be identical. Each daily grid has exactly one solution.
The rules in three lines
- Never three white or three black circles next to each other in a row or a column.
- Every row and every column has as many white circles as black ones.
- No two rows are the same, and no two columns are the same.
Takuzu is also known as the binary puzzle, binary sudoku or Binairo; the rules are the same. Besides the daily grids there are unlimited binary puzzles, free online, from 6x6 to 12x12. Full rules and a worked example.
Today's levels and our bank
Each day has 4 Takuzu puzzles, one per level below. The bank covers 512 days, from 16 October 2026 to 10 March 2028, and every one of its 2,748 puzzles was checked for a single solution by a separate program before it shipped.
| Daily puzzle | Size | Days in the bank | Median steps | Hardest technique, most often (share) |
|---|---|---|---|---|
| Easy | 8x8 | 512 | 39 | Balance (100%) |
| Medium | 10x10 | 512 | 60 | Line analysis (100%) |
| Hard | 10x10 | 512 | 60 | No twin lines (100%) |
| Expert | 10x10 | 512 | 63 | Contradiction (100%) |
Source: the Gridaday bank, 2,048 puzzles of Takuzu graded by our solver; data as of 2026-10-17.
Two colours, three rules
With only two symbols, every cell you place is half of a decision: if it cannot be white, it is black. That makes Takuzu unusually fast at the start and surprisingly stubborn at the end, when the last rows look alike and only the no-twins rule tells them apart.
Where the difficulty comes from
Easy grids give way to pairs, sandwiches and counting. Medium ones need you to list the ways a line can still be finished. Hard ones lean on the rule people forget, that no two rows may match. Expert ones need one cell assumed and followed until a rule breaks.
Questions
Why circles and not 0 and 1?
Circles are quicker to read at a glance and work for colour-blind players: white circles are rings, black circles are filled discs. Keys 0 and 1 still work on a keyboard.
Is the half-and-half rule really needed?
Yes. Our solver uses all three rules, and a puzzle may rely on any of them. The counters at the end of each row and column show how many of each colour you have placed.
Can a puzzle have two solutions?
Not here. Every grid is checked by a separate counting program that searches for a second solution before it ships.