Easy Anti-Consecutive Sudoku

Adjacent cells — horizontally or vertically — cannot contain consecutive digits. Adds a hidden constraint to every placement.

Easy Medium Hard Expert

New to Anti-Consecutive Sudoku? Each placement blocks consecutive digits in all four adjacent cells — start with 1s and 9s for the quickest wins.

1
4
9
3
7
2
8
6
2
9
4
1
6
5
9
5
8
7
2
9
3
3
8
4
6
8
4
2
3
8
2
5
6
9
4
2
5
8
Mistakes
0/3
Score
-
Time
00:00
Try Medium →
Progress0%

What is Anti-Consecutive Sudoku?

Difficulty
★★★☆☆
3/5
Constraint Type
Anti-Constraints
Typical Givens
18–24
Avg. Solve (Easy)
5 min

Solving Techniques for Easy Level

Technique Description Level
Global Candidate Pruning For every filled cell, remove its ±1 neighbours from all orthogonally adjacent cells immediately. Beginner

Ready to go deeper? Try Medium Anti-Consecutive Sudoku to unlock Intermediate techniques.

Average Solve Time by Difficulty

Easy
5 min
Medium
13 min
Hard
26 min
Expert
48 min
Want a full walkthrough of rules, strategies, and solving steps? How to Play Anti-Consecutive Sudoku →

Frequently Asked Questions — Easy Anti-Consecutive Sudoku

What is Anti-Consecutive Sudoku?
Anti-Consecutive Sudoku adds one rule to standard Sudoku: no two orthogonally adjacent cells (sharing an edge) may contain consecutive digits. If a cell holds 5, its four direct neighbors cannot contain 4 or 6. All standard Sudoku rules still apply.
How do I apply the anti-consecutive rule while solving?
Whenever you place a digit, remove its two consecutive neighbors (digit minus 1 and digit plus 1) from the candidate lists of all four orthogonally adjacent cells. This often eliminates several candidates at once and reveals new singles.
How is Anti-Consecutive Sudoku different from regular Sudoku?
Regular Sudoku only restricts repeats within rows, columns, and boxes. Anti-Consecutive Sudoku also restricts digits that differ by exactly 1 from appearing in adjacent cells. The consecutive constraint creates additional local restrictions that make placements more logical and eliminate many otherwise valid configurations.
Does the anti-consecutive constraint show on the board?
No — the constraint is invisible. Unlike some variants with visible markers on shared edges, Anti-Consecutive Sudoku applies the rule globally to every pair of edge-sharing cells without any visual indicator. You must remember to apply it universally.
How do I get started on an easy Anti-Consecutive Sudoku?
Start with the digits 1 and 9 — they only have one consecutive neighbor each (2 and 8, respectively). Placing a 1 prevents 2 from appearing in all four adjacent cells, giving you four extra eliminations. Look for areas where 1 or 9 is nearly forced by row/column/box constraints, then confirm with the consecutive rule.

More questions? See the full Anti-Consecutive Sudoku guide.