Mini Sudoku: today's 6×6 puzzle, free

How to play Mini Sudoku

Tap a cell, then tap a number (or type it). Every row, every column and every 2×3 box must contain 1 to 6 exactly once. Turn on Notes to pencil in candidates; placing a number clears it from the notes around it. A number that breaks a rule is hatched in red until you fix it. Full rules, the deductions and three practice boards on the how to play page.

Want another one? Unlimited Mini Sudoku has 1,900 puzzles in four difficulties. Missed a day? Every past day is in the archive.

The week's puzzles

Mini Sudoku strategy and tips: how to solve a 6×6 fast

A 6×6 Sudoku is solved by singles: on 97% of our hard daily boards the whole grid falls to “this cell can only hold one number” and “this number has only one cell left in this unit”, with no pencil marks, pairs or X-wings needed. The rules are the 9×9 ones scaled down, 1 to 6 once in every row, every column and every 2×3 box, and the small size is what makes it a speed game rather than a notation game. These are the scanning habits that make a Mini Sudoku take two minutes instead of ten, with numbers from a year of Puzzlune's daily boards.

How is 6×6 Sudoku different from 9×9?

The boxes are 2 rows by 3 columns, so a box shares its two rows with one other box and its three columns with two others, and every unit has only six cells. That means fewer candidates per cell, more singles, and far fewer of the advanced patterns that 9×9 needs: on our boards naked pairs, pointing pairs and X-wings almost never appear, even in Expert (91% of Expert boards are singles only). The difference between Easy and Hard is clues, 14.4 given on Easy against 10 on Hard, and the number of hidden singles you have to find, 0 per Easy board against 4.9 per Hard.

Where do you start a Mini Sudoku?

With the number that appears most often in the clues. If a number is given four times, the two remaining copies each have a row, a column and a box to fit, and usually only one cell survives all three; that is a hidden single and it is the fastest move on the board. Then take the unit with the most clues: a row with four given has two open cells and two missing numbers, and the columns of those cells decide which goes where.

What is a naked single, and what is a hidden single?

A naked single is a cell where five of the six numbers are already in its row, column or box, so only one is left; a hidden single is a number that has only one possible cell left inside a row, column or box, even if that cell could take other numbers. Our solver uses about 21.1 naked singles and 4.9 hidden singles on a Hard board. Naked singles are found by looking at a cell and asking what is missing; hidden singles by picking a number and asking where it can still go. Alternate between the two kinds of scan and you will not get stuck.

How do you scan for hidden singles in 2×3 boxes?

Pick a number and cross-hatch: for each box that does not have it yet, cross out the rows and columns where it already sits. A box is two rows tall, so one row-copy of the number already eliminates half the box; a second copy in one of the box's three columns often leaves a single cell. Do this for the numbers with the most clues first. On a Hard board with 10 clues that scan alone places the first five or six digits.

Do you need pencil marks in Mini Sudoku?

Rarely. Only 3% of Hard daily boards need anything beyond singles, and the rare case is a naked pair (two cells in a unit that share the same two candidates, which removes those candidates elsewhere in the unit). Notes mode is there for those boards and for Expert in practice mode, where about 9% of boards need a pair. If you find yourself writing notes on a Monday, you have missed a single: go back to scanning by number.

How do Mini Sudoku hints work?

A hint first checks for conflicts, two of the same digit in a unit, and highlights them; then for a wrong digit against the solution; and only then teaches the next technique, dimming the board and explaining the single it found, filling the cell when you tap “Fill it in”. The daily allows three. Conflicts are shown live as you type, by rule, not by comparing with the answer, so a red slash always means a real contradiction you can reason about.

Mini Sudoku daily, Mini Sudoku practice or the Mini Sudoku archive: which should you play?

Play the daily when you have five minutes, practice when you want to get better, the archive when you want a worked example. The daily. One 6×6, Easy on Monday and Tuesday, Medium midweek, Hard from Friday, the same for everyone. It is the only mode that counts for your streak, and the one to share.

Endless practice. Easy, Medium, Hard and Expert boards, as many as you like, with notes and undo. Nothing you do there spoils the daily.

The archive. Every past daily with the techniques named, the first moves in order and the solved grid. Every page has the full solution, so it doubles as a worked example when a technique from the strategy above hasn't clicked yet.

Mini Sudoku FAQ

What is Mini Sudoku?

Mini Sudoku is Sudoku on a 6×6 grid. Fill every row, every column and every 2×3 box with the numbers 1 to 6, each exactly once. Every puzzle has one solution and can be solved by reasoning alone, in a few minutes.

Is this the LinkedIn Mini Sudoku?

No. LinkedIn publishes one hand-made Mini Sudoku a day with no archive and no unlimited mode. Puzzlune uses the same 6×6 format with puzzles we generate and grade ourselves: one daily puzzle, unlimited mode in four difficulties, hints that explain the logic, and a free archive. We are not affiliated with LinkedIn or Nikoli.

How is difficulty decided?

Every puzzle is solved by a program that only uses human techniques. Easy puzzles fall to "this cell has one option"; Medium needs a few "this number has one place in the row" scans; Hard has fewer givens and needs several; Expert needs pencil-mark techniques such as naked pairs or pointing. Nothing ever needs a guess.

How do hints work?

A hint never fills a random cell. It first checks for mistakes, then finds the next deduction a person could make, dims the board around the cells involved and explains it in one sentence. You can apply it or do it yourself. The result card records how many hints you used.

Is this 6×6 Sudoku the same as LinkedIn Mini Sudoku, sudoku mini or minisudoku?

Same rules: 1 to 6 once in every row, column and 2×3 box. Mini sudoku 6x6, sudoku mini, minisudoku and daily mini sudoku are all searches for this puzzle; LinkedIn publishes one a day, and Puzzlune Mini Sudoku has its own boards with a free daily, four difficulties in practice mode and an archive of every past day with the techniques explained.

Do I need an account?

No. Progress, streak and stats are stored in your browser.