Practice Swordfish Sudoku Technique

Practice: Swordfish Sudoku Technique

Ready to put the swordfish technique into action? This page is designed for you to practice and master swordfish patterns with real Sudoku puzzles.

Quick Reminder: What is a Swordfish?

A swordfish occurs when a candidate number appears in only three columns within three different rows (or vice versa). When you spot a swordfish, you can eliminate that candidate from all other cells in those columns (or rows).

Want a full step-by-step guide? Read the Swordfish Technique article

How to Practice

  1. Scan the grid for a candidate that appears in only three columns within three rows (or three rows within three columns).
  2. Eliminate that candidate from all other cells in those columns (or rows).
  3. Use these eliminations to unlock more singles and progress in the puzzle.

Start Practicing

Try the puzzles below and focus on finding and applying swordfish patterns. The more you practice, the easier it will be to spot this advanced technique in any Sudoku!

Now that you know how to apply this strategy, see if you can find it on one of our Sudoku puzzles!