Naked Single Practice Puzzles

Every puzzle below is verified to feature the Naked Single as its hardest required technique — of the 65,284 puzzles in our library, 65,284 require it and 1,182 need nothing harder. New to the pattern? Learn the Naked Single or see a worked example first.

How to drill the Naked Single

Drilling Naked Singles is unlike drilling anything else on this site, because the difficulty is never in seeing the pattern. A cell with one candidate left is unmissable. The difficulty is in the bookkeeping that keeps them coming.

Almost every puzzle in the library requires them, so a puzzle listed here is one that needs nothing harder — which makes these the right grids for building placement rhythm rather than pattern recognition. The skill worth practising is the re-scan. The moment you place a digit, every peer in its row, column and box has changed, and a solved cell very often creates the next Naked Single two or three cells away. Most lost time comes from placing a digit and then restarting a fresh global sweep instead of following the chain outward from what just changed.

Try these without pencil marks if you can stand it. The constraint forces you to hold the row-column-box intersection in your head, which is the habit every later technique is built on.

Curated Naked Single puzzles

  1. Practice puzzle #1 — 24 givens · needs Naked Single
  2. Practice puzzle #2 — 25 givens · needs Naked Single
  3. Practice puzzle #3 — 24 givens · needs Naked Single
  4. Practice puzzle #4 — 26 givens · needs Naked Single
  5. Practice puzzle #5 — 24 givens · needs Naked Single
  6. Practice puzzle #6 — 25 givens · needs Naked Single
  7. Practice puzzle #7 — 23 givens · needs Naked Single
  8. Practice puzzle #8 — 25 givens · needs Naked Single
  9. Practice puzzle #9 — 23 givens · needs Naked Single
  10. Practice puzzle #10 — 24 givens · needs Naked Single
  11. Practice puzzle #11 — 26 givens · needs Naked Single
  12. Practice puzzle #12 — 23 givens · needs Naked Single
Get a fresh Naked Single puzzle →

Naked Single practice FAQ

How many Sudoku puzzles require the Naked Single technique?
Of the 65,284 puzzles in the Precision Sudoku library, 65,284 require the Naked Single to solve, and 1,182 can be completed with nothing harder than the Naked Single. Every puzzle is verified by a solver that records the exact techniques needed.
Are Naked Single puzzles too easy to be worth practising?
Not if you use them for rhythm rather than difficulty. Because no harder technique interrupts, these grids isolate the one skill every solve depends on — following the cascade of placements that one digit unlocks — and they are the only puzzles where you can rehearse it without a pattern hunt breaking your concentration.
Should I use pencil marks on Naked Single puzzles?
Try without. A Naked Single is defined as a cell with one candidate remaining, so marking every cell does the work for you and removes the exercise entirely. Solving these unmarked trains the mental row-column-box scan that makes heavily marked puzzles much faster later.