▪ King-Size Sudoku ▪ 16 × 16 ▪ Three Variants ▪ Daily Puzzles ▪

Master
the Grid

King-Size 16×16 Sudoku. Three Variants. One Daily Challenge.

Free printable 16×16 Sudoku PDFs across five difficulty levels — Easy, Medium, Hard, Extreme, and Super Extreme. Choose your variant: Killer cages with sum constraints, irregular Jigsaw regions, or Thermo & Arrow rules. Every puzzle has a unique solution. No guessing required.

🔥 Killer Sudoku — Live 🧩 Jigsaw Sudoku — Live 🌡️ Thermo & Arrow — Coming Soon
Explore Variants Why 16×16?
// Choose Your Variant

Free 16×16 Killer, Jigsaw & Thermo Sudoku

Every puzzle on Master the Grid uses a 16×16 board — the difference is the extra constraints layered on top.

🔥
● Live Now
Killer Sudoku
King-Size 16×16 • Cage Sums
King-Size 16×16 Killer Sudoku sample puzzle
Cells are grouped into cages. The digits inside each cage must sum to the number shown. No digit repeats within a cage. Combined with the 16×16 base rules, this creates extraordinary depth and requires both arithmetic and logical reasoning.
Explore Killer →
🧩
● Live Now
Jigsaw Sudoku
King-Size 16×16 • Irregular Regions
King-Size 16×16 Jigsaw Sudoku sample puzzle
Instead of neat 4×4 boxes, regions are irregular jigsaw-shaped polyominoes. Each oddly-shaped region must still contain every digit from 1 to 16. The asymmetry forces completely different solving strategies.
Explore Jigsaw →
🌡️
Coming Soon
Thermo & Arrow
King-Size 16×16 • Path Constraints
King-Size 16×16 Thermo & Arrow Sudoku sample puzzle
Thermometer lines require digits to increase from bulb to tip. Arrow circles must equal the sum of digits along the arrow's path. One of the most visually striking and strategically demanding Sudoku formats.
// The Format

Why 16×16 Sudoku is the Ultimate Challenge

We focus exclusively on 16×16 Sudoku — because that's where the real depth begins.

⊞

256 Cells. 16 Symbols.

Every row, column, and 4×4 box must contain each digit from 1 to 16 exactly once. The expanded symbol set forces solvers to track far more interdependencies simultaneously.

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Strategic Depth

Techniques that trivially solve 9×9 puzzles — naked pairs, hidden singles — become intricate multi-step chains in a 16×16 grid. Every move carries more consequence.

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Three Extra Constraint Layers

Killer cages, Jigsaw regions, and Thermo/Arrow paths each add a completely different logical dimension on top of the 16×16 base — three distinct puzzle experiences.

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Five Difficulty Tiers

From approachable Easy grids for newcomers to the 16×16 format, all the way to Super Extreme puzzles that will challenge even the most seasoned veterans.

Full Guide: Why King-Size? →
// Planned Feature Phase 2

Coming Soon: Play Online

An interactive, browser-based King-Size Killer Sudoku — 16×16, fully featured, no install required.

💡Smart Hints — context-aware logical suggestionsSoon
✏️Pencil Marks — full notes mode per cellSoon
✔️Auto-Check — instant conflict highlightingSoon
↩️Undo / Redo — full move historySoon
⏱Timer & Scoring — track your personal bestsSoon
🔢Killer Cages — sum constraints on the 16×16 gridSoon

🔔 Get Notified

Be the first to play when the online game launches.

Master the Grid — Online (Preview)
KILLER 16×16 • HARD ⏱ 00:00

Development Preview

The interactive Killer Sudoku engine is in active development. Sign up above to join the waitlist.

// Get in Touch

Contact

Questions, puzzle requests, or feedback — we'd love to hear from you.

We're building this for puzzle lovers.

Master the Grid is a passion project dedicated to King-Size Sudoku. Every puzzle is hand-verified for a unique solution.

✉ [email protected]
🐛
Report a puzzle error
Found a mistake? Let us know the puzzle ID.
💡
Request a variant
Have another King-Size format in mind? Ask away.
📦
Bulk PDF packs
Classroom or club use? We can prepare packs.