Ultimate Sudoku — Play Free Online

Ultimate Sudoku is a straightforward take on the classic number puzzle: fill the 9×9 grid so that every row, column and 3×3 box contains the digits 1 to 9 exactly once. There is no story, no character and nothing to dodge. It is a quiet, thinking-only game, which makes it an odd but welcome neighbour on a site built around Doodle Jump's frantic climbing.

The build offers three difficulty modes: beginner, intermediate and advanced. Each one has a time target used to work out bonus points, so a clean, quick solve scores better than a slow one, and the game also keeps track of how many hints you leaned on. If you only want to relax, you can ignore the clock and simply enjoy the puzzle; if you like a little pressure, the timer gives you something to beat.

It runs in the browser with nothing to install, and a full grid fits comfortably into a short break, though advanced boards can take much longer than the ten, twenty and thirty minute bonus windows suggest if you are new to the genre.

How to play

This is a pointer game, not a keyboard one. Pick a cell by clicking or tapping it, then choose the number you want to place. The arrow-key and WASD line in the catalogue entry is generic text that does not describe a sudoku board, so rely on the mouse or your finger.

Start by choosing a mode. The game fills the grid with starting digits that cannot be changed. Your job is to place the missing ones without repeating a digit in any row, column or box. The game includes helper features: an option to fill in candidate notes automatically, hints, and a solve option. Using them lowers your score, so treat them as a safety net rather than a routine.

Tips

• Scan for the digit that appears most often on the board and look for where its missing copies must go. Rows and boxes crowded with one number narrow the options quickly.
• Look for cells where only one digit fits because the rest are already in the same row, column or box. These "naked singles" carry beginner and intermediate boards.
• On advanced boards, work with candidate notes. If a digit can only go in one cell inside a box, it belongs there, even if that cell has other candidates.
• Do not guess. A wrong placement usually surfaces many moves later and is painful to untangle, so find a forced move instead.

Similar games on Doodle Jump

If you want something in the same relaxed vein, Fireboy and Watergirl swaps numbers for two-character logic puzzles where you work out routes and switches. Helix Jump is much faster, asking for timing as you drop a ball through rings. Doodle Jump itself is the reflex counterpart, so sudoku is a good change of pace after a few frantic runs.

Ultimate Sudoku suits anyone who likes puzzles they can play at their own speed, on a computer with a mouse or on a phone with taps.