Sudoku365
Medium Sudoku for Thursday, May 21, 2026
Medium Sudoku · Thursday, May 21, 2026 · Solution: sudoku365.com/daily/2026/05/21/medium
About This Medium Sudoku Puzzle
This medium Sudoku for Thursday, May 21, 2026 (5/21/2026) starts with 34 given numbers and has exactly one solution. A logic solver places 29 of the 47 empty cells with 12 naked singles, 17 hidden singles, 1 swordfish and 1 y-wing before it stalls.
Hardest technique needed: beyond the guides on this site. A solver using singles, locked candidates, pairs, triples, X-Wing, Swordfish and Y-Wing stalls with 18 cells still empty, so expect to need longer chains. The puzzle still has exactly one solution.
Stuck? See the first moves
- Row 9, column 7 must be 1: every other digit is already in its row, column or box (naked single).
- Row 9, column 9 must be 3: every other digit is already in its row, column or box (naked single).
- Row 7, column 9 must be 4: every other digit is already in its row, column or box (naked single).
Show the answer to the May 21, 2026 medium Sudoku
| 4 | 3 | 1 | 8 | 2 | 7 | 5 | 6 | 9 |
| 8 | 6 | 5 | 3 | 9 | 1 | 2 | 4 | 7 |
| 2 | 9 | 7 | 5 | 6 | 4 | 3 | 8 | 1 |
| 1 | 4 | 2 | 6 | 8 | 9 | 7 | 3 | 5 |
| 5 | 8 | 9 | 7 | 3 | 2 | 4 | 1 | 6 |
| 3 | 7 | 6 | 4 | 1 | 5 | 8 | 9 | 2 |
| 9 | 2 | 3 | 1 | 7 | 8 | 6 | 5 | 4 |
| 6 | 1 | 4 | 2 | 5 | 3 | 9 | 7 | 8 |
| 7 | 5 | 8 | 9 | 4 | 6 | 1 | 2 | 3 |
Bold digits are the original clues.
Print This Puzzle
Press Print above for a clean, full-page copy of this grid — no download or sign-up needed. To get all four of this date's levels on one sheet, print the May 21 set with answers, or grab a printable Medium pack with four puzzles and their solutions. Want the answer on paper too? Print this puzzle in large print with its answer key, or print 7 days of Medium puzzles starting on this date.
How to Solve This Puzzle
Click any empty cell and enter a number from 1-9. Use logic to determine which numbers can fit in each cell based on the Sudoku rules: no repeating numbers in any row, column, or 3x3 box. Turn on Notes to pencil in candidates; they are cleared automatically when you place a digit in the same row, column or box. Stuck for good? Show Solution fills in the answer.
Keyboard Shortcuts
- 1-9: Enter number in selected cell
- Arrow Keys: Navigate between cells
- Backspace/Delete: Clear selected cell
- N: Toggle pencil-mark notes
- Ctrl+Z / ⌘Z: Undo
Tips for Medium Puzzles
- Use the Hidden Singles technique to find unique candidates
- Identify Naked Pairs to eliminate candidates
- Process one box at a time systematically
- Learn more in our Hidden Singles guide