Expert Sudoku Online
Well done!
Expert sudoku is the top shelf: only 24 numbers are given, and every grid asks for careful notes and advanced techniques. Bring patience and a cup of tea.
Who Expert Is For
Expert is for players who finish Hard grids without help and want something that really makes them think. You should be comfortable with pencil notes and know the basic solving techniques: hidden singles, pointing and pairs. If those words are new to you, spend some time on Hard Sudoku first; it will make this level far more enjoyable.
Only 24 Numbers
An expert sudoku here begins with just 24 of its 81 squares filled, less than a third of the grid. The generator removes numbers one at a time and checks after each removal that the puzzle still has exactly one solution. Then it solves the grid step by step, the way a person would, and keeps it only if singles are not enough and a long run of harder moves is needed. Every number left on the board matters.
Advanced Techniques You Will Meet
Most Expert grids open with a handful of easy moves and then go quiet. That is where the real game begins. Expect to use:
- Naked and hidden pairs to clean up crowded notes.
- Pointing to carry information from a box to a row or column.
- X Wing, where one number is limited to the same two columns in two rows.
- Swordfish, the bigger cousin of the X Wing, built on three rows and three columns.
Each technique is explained step by step with a diagram on our page about Sudoku strategies.
Extreme Sudoku, Calmly
Some websites call this level extreme sudoku and wrap it in countdowns and leaderboards. We prefer a quieter approach. The timer can be paused or hidden, there are no rankings, and nobody is waiting for you. Expert puzzles reward slow, careful thinking, and this page is designed for exactly that. If you came looking for extreme sudoku online, you will find the same tough grids here, just without the noise.
How Long a Game Takes
Allow 30 minutes to an hour, sometimes more. It is perfectly fine to solve an Expert grid in several sittings: your game, notes and timer are saved in the browser, and when you come back the board is exactly as you left it.
Want to Play Expert Sudoku Online With a Friend?
Every grid has a number shown above the board. Press Share this puzzle to copy a link, send it to a friend, and you can both solve the same puzzle and compare notes afterward. If you would rather take a step back, Hard Sudoku is one level down, and the Daily Sudoku offers one shared puzzle for everyone each day.
Expert Sudoku Questions
How is Expert different from Hard?
Expert grids start with 24 numbers instead of 27. A Hard grid needs only a few pointing or pair moves; an Expert grid needs a long chain of them, and some grids also need an X Wing or a Swordfish.
How do you make sure an Expert puzzle is really hard?
Before a grid reaches you, the generator solves it the way a person would, starting with the simplest techniques. If it can be finished with singles alone, or with just a couple of harder moves, it is thrown away and a new one is made.
Is every Expert puzzle solvable without guessing?
Yes. Every grid can be finished with the techniques explained on our strategies page, from singles to the Swordfish. It can take patience and a full set of notes, but logic alone will get you there.
How long does an Expert Sudoku take?
Usually between 30 minutes and an hour, sometimes more. The game is saved in your browser, so you can come back to it later.