Easy Hyper Sudoku

Four extra 3×3 boxes overlap the standard grid, creating additional regions that must each contain 1–9 exactly once.

Easy Medium Hard Expert

New to Hyper Sudoku? The four shaded extra regions each need 1–9 just like the standard boxes — cells inside them carry five constraints at once. Start here.

3
6
4
8
4
8
9
6
3
8
6
9
5
7
6
4
3
1
3
1
2
6
1
5
3
6
9
8
5
2
7
8
3
4
5
5
2
6
Mistakes
0/3
Score
-
Time
00:00
Try Medium Hyper Sudoku →
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What is Hyper / Windoku?

Difficulty
★★★☆☆
3/5
Constraint Type
Extra Regions
Typical Givens
26–32
Avg. Solve (Easy)
6 min

Solving Techniques for Easy Level

Technique Description Level
Region Overlap Analysis Each Hyper region overlaps with two standard 3×3 boxes. Any digit placed in the standard box cells within a Hyper region also constrains the full Hyper region. Beginner
Extended Naked Singles With 13 regions total (9 standard boxes + 4 Hyper), naked singles appear far more often than in classic Sudoku. Beginner

Ready to go deeper? Try Medium Hyper / Windoku to unlock Intermediate techniques.

Techniques to Master at Easy

  • Last Free Cell technique — With 13 box-shaped regions instead of 9, one of the four hyper windows is often a single cell from complete before any row is — scan the windows first.
  • Last Possible Number technique — Cells inside a hyper window are cross-checked against five houses, so candidate elimination frequently collapses them to one digit in a single pass.

Average Solve Time by Difficulty

Easy
6 min
Medium
15 min
Hard
30 min
Expert
55 min
Want a full walkthrough of rules, strategies, and solving steps? How to Play Hyper / Windoku →

Related Variants

Diagonal Sudoku

Extra houses again, drawn as two diagonals instead of four windows — the same scan-more-units discipline.

Jigsaw Sudoku

Region thinking taken further: the nine boxes themselves become irregular shapes you must learn to read.

Samurai Sudoku

If overlapping regions are the appeal, samurai overlaps entire grids — five of them sharing corner boxes.

Frequently Asked Questions — Easy Hyper Sudoku

What is Hyper Sudoku?
Hyper Sudoku (also called Windoku or NRC Sudoku) adds four extra 3×3 regions to the standard 9×9 grid. These four shaded regions — positioned symmetrically inside the grid — must each contain the digits 1–9 exactly once, just like the standard boxes. All standard Sudoku rules still apply.
Where are the four extra regions in Hyper Sudoku?
The four hyper regions are centered at rows 2–4 and 6–8, columns 2–4 and 6–8. They form a 2×2 arrangement of extra boxes symmetrically placed inside the grid, each offset from the standard 3×3 boxes so they overlap with multiple standard regions.
Do standard Sudoku rules still apply in Hyper Sudoku?
Yes. Every row, every column, and every standard 3×3 box must still contain 1–9 exactly once. The four hyper regions are additional constraints on top of the standard rules, giving cells inside a hyper region five constraint groups instead of three.
How do I start solving an easy Hyper Sudoku?
Focus on cells that are inside a hyper region — they carry an extra constraint and are typically the most restricted cells. Apply elimination using all five groups (row, column, standard box, and hyper region) for those cells first, then spread outward.
Why are cells inside hyper regions easier to solve first?
Cells inside a hyper region belong to five constraint groups: their row, their column, their standard 3×3 box, and their hyper region. More constraints mean more eliminations per cell, which means fewer candidates and faster placements.

More questions? See the full Hyper / Windoku guide.