The rules of Sudolito
Sudolito is played on a grid of 6 rows and 6 columns, split into six regions of 2 rows by 3 columns. A few digits are given at the start, and they are fixed. Your goal is to fill every empty cell.
- Each row contains the digits 1 to 6, once each.
- Each column contains the digits 1 to 6, once each.
- Each region of 2 × 3 cells contains the digits 1 to 6, once each.
Every grid has a single solution, checked by a solver before it is published. It can be solved entirely by deduction, without ever guessing.
The daily grid
A new grid comes out every day, the same for all players. Difficulty depends on how many digits are given at the start: around 22 for an easy grid, 17 for a medium one and 13 for a hard one. Sunday's grid is always hard; on weekdays the level varies from day to day.
Controls
Tap an empty cell to select it, then tap a digit on the keypad below the grid. On a computer you can also type 1 to 6 and move with the arrow keys.
Every digit is checked straight away:
- a correct digit locks in with a small animation, and a wave runs through the row, column or region you just completed;
- a wrong digit turns red, crossed out, and locks the grid: only the undo button stays active so you can remove it.
The keypad shows how many copies of each digit are left to place, and a check mark once a digit is done. The game controls carry French labels: Annuler (undo), Notes, Effacer (erase) and Joker.
Notes mode
Turn on Notes (or press N) to pencil candidates into a cell instead of a final digit. The game refuses an impossible note, meaning a digit already present in the row, column or region, and flashes the cells that block it. When you place a correct digit, it disappears from the notes in its row, column and region.
To note a digit in several cells at once, drag your finger across the empty cells, then tap the digit. Effacer clears the notes of the selected cells. Notes are stored on your device only.
Locking a digit
A long press on a keypad digit (or the L key) locks it: every copy is highlighted on the grid, and each empty cell you tap receives that digit. Handy for placing all the 4s in a row. The lock lifts once the digit is complete.
A region solved step by step
Take the top-left region (rows 1 and 2, columns 1 to 3). Here is what it holds at the start, with dots marking empty cells:
| Col. 1 | Col. 2 | Col. 3 |
|---|---|---|
| 1 | · | 4 |
| · | 6 | · |
The digits 2, 3 and 5 are missing. Elsewhere on the grid, row 1 already contains a 2 and a 5, in the neighbouring region, and column 1 has a 5 in row 4.
1. The cell in row 1. The only empty cell of row 1 in this region can be neither 2 nor 5, which are already in the row. That leaves 3.
2. The two cells in row 2. The 2 and the 5 remain. The 5 cannot go in column 1, which already has one, so it goes in column 3, and the 2 in column 1.
The region is complete: 1 3 4 on the first row, 2 6 5 on the second. This reasoning, crossing a region with the rows and columns that run through it, drives almost every grid forward.
How scoring works
Your score out of 1000 depends on mistakes, jokers and time. On a 6 × 6 grid each mistake costs a noticeable share of the score, roughly 20 to 35 points depending on how many cells were empty.
The Joker reveals the digit of the selected cell if it is empty, otherwise another open cell. Jokers are unlimited, but each one costs about 60 points. The reference time is 3 minutes on easy, 5 on medium and 7 on hard: finishing twice as fast earns the maximum 20% bonus.
What next?
To improve, read our Sudolito tips. When the 6 × 6 format feels too easy, move up to classic 9 × 9 sudoku with Sudoko, or explore our pick of daily logic games.