Mini Sudoku is a free iPhone puzzle app that offers five Sudoku variants: the compact 6×6 Mini grid, Classic 9×9, Sudoku X, Killer Sudoku, and Jigsaw Sudoku, plus a Special endless survival mode.

What is Special mode in Mini Sudoku?

Special mode is an endless survival challenge. You must fill in at least one cell within a countdown timer before time runs out. Each completed 6×6 grid loads a new, harder one — see how many grids you can clear.

What Sudoku variants are available?

Mini Sudoku includes five variants: 6×6 Mini Sudoku, Classic 9×9 Sudoku, Sudoku X (diagonal constraint), Killer Sudoku (sum cages), and Jigsaw Sudoku (irregular regions). Each has Easy, Medium, and Hard difficulty.

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Mini Sudoku

Five Sudoku variants. One elegant app. Play the compact 6×6 Special mode or go deep with Classic, Sudoku X, Killer, and Jigsaw puzzles.

6×6 Mini Grid 5 Game Modes Free to Play No Account Needed Easy · Medium · Hard

Grid 3 · Easy 11s

Special Mode — fill a cell before time runs out

Special Mode

Endless survival — how many grids can you clear?

Special mode turns a calm puzzle into a pulse-raising survival challenge. You must fill in at least one cell before the countdown hits zero — or it's game over.

Every completed 6×6 grid loads a new one instantly. The difficulty escalates and the timer gets tighter the further you go.

Grids 1–5 are Easy, 6–10 are Medium, 11+ are Hard

15 seconds per move for grids 1–15

Drops to 10 seconds from grid 16–20

Only 5 seconds per move from grid 21 onward

Grid 4 · Easy 13s

Grids 1–5

Easy 15s / move

Grids 6–10

Medium 15s / move

Grids 11–15

Hard 15s / move

Grids 16–20

Hard 10s / move

Grids 21+

Hard 5s / move

Relax Mode

Five puzzle variants — no timer, no pressure. Just pure logic.

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6×6 Grid

Mini Sudoku

The classic Sudoku format shrunk to a 6×6 grid with 2×3 boxes. Perfect for a quick puzzle session. Fill every row, column, and box with digits 1–6.

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9×9 Grid

Classic Sudoku

The original 9×9 puzzle with 3×3 boxes. Fill every row, column, and box with digits 1–9. The gold standard of logic puzzles, from beginner to expert.

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Diagonal Constraint

Sudoku X

Classic Sudoku with an extra rule — both main diagonals must also contain each digit exactly once. A twist that demands an entirely new layer of thinking.

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Sum Cages

Killer Sudoku

No given numbers — instead, dotted cages show the sum of the cells inside. Digits in a cage cannot repeat. Arithmetic meets logic in the toughest variant.

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Irregular Regions

Jigsaw Sudoku

Standard 3×3 boxes are replaced by irregular jigsaw-shaped regions. The uniquely shaped groups force you to rethink every deduction from scratch.

How to Play

Simple rules. Satisfying logic.

Fill the Grid

Place digits so that every row, every column, and every outlined region contains each number exactly once — no repeats anywhere.

Tap a Cell

Select any empty cell, then tap a number from the pad below. Conflicts are highlighted automatically so you can spot mistakes immediately.

Use Notes

Toggle Notes mode to pencil in candidates. Mark multiple possibilities in a cell, then eliminate them as you narrow down the answer.

Get a Hint

Stuck? Tap Hint to reveal one correct cell. Watch a short ad for a free hint, or upgrade to Premium for unlimited hints.

Choose Your Challenge

Every Relax mode variant has three difficulty levels.

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Easy

More given digits and straightforward deductions. Great for newcomers or a relaxing session.

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Medium

Fewer givens and more complex chains. A satisfying challenge for regular solvers.

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Hard

Minimal givens and advanced techniques required. For dedicated puzzle enthusiasts only.

Everything You Need

Thoughtfully designed for daily puzzle play.

✏️ Notes Mode

Pencil in candidate numbers with a single tap. Notes stay visible as you work through deductions, just like solving on paper.

💡 Smart Hints

Tap Hint to reveal one correct cell. Watch a short ad for a free hint, or go Premium for unlimited access — your call.

📊 Detailed Stats

Track your Special mode best score, grids cleared per difficulty, and per-mode win counts with best times across all five variants.

📳 Haptic Feedback

Crisp, satisfying vibration on every input. Toggle sound and haptics independently in Settings.

🔒 No Account Needed

No sign-up, no cloud sync, no tracking beyond your device. Just open the app and play.

⭐ Premium Mode

Remove ads and unlock unlimited hints with a one-time Premium upgrade. Solve without interruption.

Frequently Asked Questions

What is Mini Sudoku?

Mini Sudoku is a free iPhone puzzle app with five Sudoku variants: a compact 6×6 Mini grid, Classic 9×9, Sudoku X, Killer Sudoku, and Jigsaw Sudoku. It also features a Special endless survival mode.

What is Special mode?

Special mode is an endless 6×6 survival challenge. You must fill in at least one correct cell before the per-move countdown hits zero. Grids keep coming — difficulty and time pressure increase the further you go.

Is Mini Sudoku free?

Yes. Mini Sudoku is free to download and play. An optional Premium upgrade removes all ads and unlocks unlimited hints.

What is Killer Sudoku?

Killer Sudoku replaces the given digits with dotted cages, each showing the sum of the cells inside. Cells within a cage cannot repeat. It's the hardest variant — arithmetic and logic combined.

What is Sudoku X?

Sudoku X adds one rule to Classic Sudoku: both main diagonals (top-left to bottom-right, and top-right to bottom-left) must each contain every digit exactly once. This extra constraint opens new solving paths.

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