Sudoku that explains itself.
Most sudoku sites hand you an answer. Here, every hint names the technique and shows you why it works — so the next puzzle is easier than the last.
Pick your level
Difficulty is measured by the techniques a puzzle forces you to use — not by guesswork.
Hints that teach
Every hint is generated from your actual position, using the same engine that rates the puzzles.
Fresh every day
One new puzzle every day, generated from the date so everyone gets the same board. The archive goes back to January 2026.
Built to be fast
No frameworks, no trackers, no ad scripts. The whole game is a few kilobytes of JavaScript, so it starts instantly on a phone and works offline once loaded.
Frequently asked
Is Sudoku Atelier really free?
Yes — every puzzle, every hint, every level. There are no ads, no paywalls and no account. The site is static and runs entirely in your browser.
How are the difficulties rated?
Each puzzle is solved by a simulator that only uses techniques a person can do by hand — singles, locked candidates, pairs, fish, wings. The hardest technique required sets the level, and fewer clues pushes it up one step.
What makes the hints different?
A hint names the technique, explains why it applies to your current board, and highlights the cells involved. You can then place the digit yourself, or ask it to place it for you.
Does it work offline?
Yes. The site is a PWA: after your first visit the shell is cached, and puzzles you have opened keep working without a network.
Can I play with a keyboard?
Arrow keys move, 1–9 fill, Backspace erases, N toggles notes, H gives a hint, Space pauses.