Sudoku Washi: Daily Puzzle

Sudoku Washi is a calm, fully offline number puzzle you can play anywhere. No connection, no account, no login. Open the app and a board is ready at once. On the subway, on a plane, or far from any signal, you can sit quietly with the numbers without worrying about data. No noisy pop-ups breaking your focus — just clean, considered Sudoku.

How to play Fill the 9x9 grid with the numbers 1 to 9. Each row, each column, and each bold 3x3 block must contain every number exactly once. Starting from the given numbers, you fill the rest with logic alone. No luck and no hard arithmetic — only the calm of checking one cell at a time.

Today's Puzzle The heart of the app is Today's Puzzle. The board is built from the day's date, so without any server, players all over the world face the exact same puzzle each day. Tomorrow brings a fresh one. It is a small daily ritual you can share with everyone, while staying completely offline.

Daily streak Clear Today's Puzzle day after day and your streak grows. That small wish not to break the chain quietly keeps the habit alive. Your current streak is always visible on the home screen.

Four difficulties Easy, Normal, Hard and Demon. Every board is generated by an algorithm and guaranteed to have a single unique solution, so there are endless fresh puzzles — you will never run out. Pick a level to match your mood and focus.

Gentle helpers for newcomers

• Pencil notes: jot small candidate numbers inside a cell, just like scribbling in the margin on paper.
• Mistake highlighting: when a number clashes in its row, column or block, the color changes on the spot.
• Hint: stuck? It fills in one correct number for you.
• Auto-candidates: fills every empty cell with its possible notes, to set up your thinking.
• Undo: step back a move whenever you slip. Use them or ignore them — lean on the helpers, or solve everything yourself. It is up to you.

Paper and Dark themes A calm washi-paper look, like ink on natural-colored paper, and an eye-friendly Dark theme, switched with a single tap. Your choice is remembered, so there is nothing to set again.

Best times saved Your finishing time is saved as a personal best for each difficulty. Beat your previous time and you get a best-updated message. A quiet time attack against yesterday's you.

A pleasant feel Place a number, make a mistake, or solve the whole board — each moment carries its own subtle haptic feedback, so you feel the satisfaction of that final cell in your fingertips.

Privacy The app works fully offline. Your records — best times, daily streak, theme and language — are stored only on your device. Nothing is collected and nothing is sent anywhere. Just settle in and focus on the puzzle.

Frequently asked

• Can I play offline? Yes. Every feature works without a connection, even in airplane mode.
• How many puzzles are there? Boards are generated on the fly, so there is no limit.
• New to Sudoku? Notes, mistake highlighting, hints and auto-candidates let you learn as you go.
• Do my records stay? Best times and streaks are saved on your device and survive closing the app.
• Which languages? English and Japanese, following your device automatically, with a manual switch in the app.

Who it's for

• Anyone who wants a little brain exercise in spare moments
• Players tired of ad-heavy games, looking for quiet Sudoku
• People who want a small daily habit they can keep
• Anyone needing an offline puzzle for places with no signal
• First-timers who want gentle, built-in guidance

One quiet move at a time. Let today's puzzle keep you gentle company. Make daily Sudoku your habit with Sudoku Washi.