About Sudoku AZ

A small site with a single purpose: good Sudoku you can play in your browser, free, on any device.

What this site is

Sudoku AZ is a collection of hand-built Sudoku games: the classic 9×9 puzzle in three difficulty levels, plus four genuine variants — Color Sudoku, Killer Sudoku, Chain Sudoku and Flower Sudoku. Each one is a real, distinct game with its own rules and its own solving logic, not the same board wearing a different coat of paint. The domain has been home to browser Sudoku since the mid-2010s, and this is its modern incarnation: no Flash, no plugins, nothing to install.

How the puzzles are made

Every puzzle on this site is generated with a guaranteed unique solution and verified by a solver before you ever see it. That is a promise about fairness: you will never need to guess, and logic alone is always enough to finish a board. Difficulty levels are set by how many clues you start with and which techniques the board demands, so an easy puzzle is genuinely easy and an expert one genuinely earns its name.

How the site works

• Free, with no account. Your progress, statistics and preferences are saved locally in your own browser, and nowhere else.
• No tracking. The site loads no third-party analytics, no ad networks and no external scripts of any kind.
• Fast by design. Each game ships as a single small file, so it starts instantly even on a slow connection.
• Works everywhere. Phone, tablet or desktop, with a light and a dark theme that follows your system preference.

Why Sudoku, and why here

Sudoku endures because it asks so little and gives so much. There is nothing to learn beyond one rule, no language barrier, no equipment, and yet the puzzle can absorb five minutes or fifty. The trouble is that a lot of places to play it online are cluttered — heavy with ads, pop-ups, sign-up walls and trackers that get between you and the grid. Sudoku AZ exists to strip all of that away and leave just the game: open the page, and you are already playing. That single idea shapes every decision here, from the fast single-file games to the quiet, uncluttered layout.

What we care about

Three things guide the site. The first is fairness: every board is verified to have exactly one solution reachable by logic, so your time is never wasted on a puzzle that needs a guess. The second is speed: each game loads as one small file and starts instantly, even on a slow phone on a train. The third is respect for your attention: no autoplay, no nagging, no dark patterns designed to keep you scrolling. A puzzle you finish and close cleanly is a good outcome, not a lost one, and the site is built to treat it that way.

Free, and staying that way

Everything here is free to play, with no account required and nothing to install. Your solve times, statistics and preferences live only in your own browser, so they follow you between sessions without ever being uploaded. New variants and features are added over time — the growing family of games, the Daily puzzle, and short guides and tips for players who want to improve — but the core promise stays the same: a clean, fast, honest place to play Sudoku on any device. It is a small project made and maintained with care, and it will keep growing one considered feature at a time rather than chasing every trend.

Get in touch

Found a bug, or have an idea for a variant you would like to play here? Feedback is always welcome — write to [email protected].