Sudoku Patterns You Should Know

Patterns reduce search time. When you know what to look for, hard puzzles become systematic.

Singles

• Naked singles: one candidate in a cell.
• Hidden singles: one location for a candidate in a unit.

Locked Candidates

If a candidate in a box is limited to one row or column, remove it from that row/column outside the box.

Pairs

Two cells in a unit sharing same two candidates let you remove those candidates from other cells in that unit.

Triples

Three cells sharing a 3-number set create the same elimination principle as pairs, on a larger footprint.

When to Use Which Pattern

• Early game: singles first.
• Mid game: locked candidates + pairs.
• Late game: triples and deeper eliminations.

Practice one pattern per day inside Sudoku One9x for stronger retention.

Pattern Practice Rotation

Do not try to master every pattern in one week. Rotate focus by day: singles day, locked-candidate day, pair day, triple day, then mixed day. This builds pattern fluency without overload.

• Single-pattern sessions improve recognition speed.
• Mixed sessions improve pattern switching.
• Short review notes lock in pattern memory.

How to Know a Pattern Is Learned

You stop searching for it and start seeing it automatically during scans. That shift is the real milestone. Use Sudoku One9x for repeated exposure across puzzle difficulties.

Pattern Priority by Difficulty

For easy puzzles, singles dominate. For medium puzzles, locked candidates and pairs become key. For hard puzzles, pattern chaining and disciplined candidate cleanup become essential. Matching pattern depth to puzzle difficulty prevents both under-solving and overcomplicating.

Retention Tip

After each puzzle, write the one pattern that produced the biggest breakthrough. This reinforces recall and speeds up pattern detection in future games.