Sudoku set
X-Sudoku 6x6 — Extreme
Vocabulary List with 20 words
Extreme 6x6 X-Sudoku with minimal given digits. Every placement requires multi-step reasoning across diagonals, rows, columns, and boxes simultaneously.
How to Use This Worksheet
- Print: Click the print button to get a clean printout perfect for students
- Practice: Complete the practice exercises
- Check Answers: Review with students or use for self-checking
- Download PDF: Save a copy for offline use or printing later
Learning Benefits
This sudoku puzzles builds focused practice, confidence, and independent problem-solving skills.
X-Sudoku — Free Online & Printable
X-Sudoku adds a diagonal constraint to the classic sudoku rules. Both main diagonals — running from top-left to bottom-right and from top-right to bottom-left — must each contain the numbers 1 through 9 without repetition. This is the most accessible sudoku variant: the two extra constraints actually make many cells easier to deduce, since numbers on the diagonals are additionally restricted. If you''ve mastered standard sudoku and want a fresh twist without learning complex new rules, X-Sudoku (also called Diagonal Sudoku) is the ideal starting point.
About 6x6 Grid
The 6x6 grid strikes a balance between accessibility and depth. With 36 cells in 2x3 boxes, puzzles take 3 to 10 minutes depending on difficulty. The 6x6 is large enough to showcase variant rules meaningfully — Killer cages have room to create genuine arithmetic puzzles, Windoku windows overlap in interesting ways — while remaining completable in a single sitting. Many players find the 6x6 their "daily driver" format: challenging enough to be satisfying, short enough to fit into a break.
Extreme Difficulty
Extreme difficulty represents the hardest puzzles solvable through pure logic — no guessing required, but the reasoning chains are exceptionally long. Required techniques include forcing chains (sequences of implications that eliminate candidates by showing they lead to contradictions), multi-step coloring, and in some cases trial-and-error with backtracking when chains become impractical to track mentally. These puzzles are designed for experienced competitors and dedicated enthusiasts. Average time: 60+ minutes. Even experienced solvers may spend 10-15 minutes without making a single cell entry while planning a deduction chain.
How to Get Started
- Choose "New Puzzle" to generate a fresh puzzle with a unique solution
- Click or tap cells to enter numbers (1-6 for 6x6)
- Use the constraint highlights to track which numbers are still available
- Print the puzzle if you prefer solving on paper
How to use this printable Sudoku set
Best for logic practice, print-and-solve puzzle books, classroom challenges, and variant Sudoku exploration.
- Print the grid, solve with notes, then reveal or compare answers only after a full solving attempt.
- Start with classic Sudoku, then branch into X, Hyper, Jigsaw, Killer, and other rule variants.
- Use the previous and next set links to stay inside the same page family before jumping to broader hubs.
Answer key policy
Answer support is available for review after a real attempt; printable answer-key behavior depends on the activity type.
Same-family next steps
Use the previous and next set links to stay inside the same page family before jumping to broader hubs.
Measurement events
This page should measure landed, started, used hint, checked answer, completed, printed/downloaded, shared, and clicked next events when the matching controls exist.
Sudoku variant cluster