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Daily Sudoku — 11 October 2026

The puzzle

  • 11 October 2026
  • Hard
  • 30 clues
Puzzle
·1·847·6·
9···3·4··
8··9···1·
····796·3
·2····79·
···36···4
75·······
··912····
142····3·
Solution
213847569
965231478
874956312
481579623
326418795
597362184
758693241
639124857
142785936

Solve it in the app to get on the board

Step-by-step solution

Every cell below is filled by the same hint engine the app uses, in the order it can be deduced — 51 steps using 2 techniques.

Techniques used

  • Hidden Single — inside one row, column or box this digit fits in only one cell, so it must go there
  • Naked Single — every other digit is already used in this cell's row, column or box, so only one candidate is left
  1. R1C1 = 2 · Hidden SingleIn the top-left 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because column 3 already has a 2, R1C3, R2C3 and R3C3 cannot hold 2.- Because column 2 already has a 2, R2C2 and R3C2 cannot hold 2.So 2 must go in R1C1.
  2. R3C3 = 4 · Hidden SingleIn the top-left 3×3 box, 4 fits in only one cell. Looking at the other empty cells:- Because row 1 already has a 4, R1C3 cannot hold 4.- Because row 2 already has a 4, R2C2 and R2C3 cannot hold 4.- Because column 2 already has a 4, R3C2 cannot hold 4.So 4 must go in R3C3.
  3. R2C6 = 1 · Hidden SingleIn the top-centre 3×3 box, 1 fits in only one cell. Looking at the other empty cells:- Because column 4 already has a 1, R2C4 cannot hold 1.- Because row 3 already has a 1, R3C5 and R3C6 cannot hold 1.So 1 must go in R2C6.
  4. R6C2 = 9 · Hidden SingleIn the middle-left 3×3 box, 9 fits in only one cell. Looking at the other empty cells:- Because row 4 already has a 9, R4C1, R4C2 and R4C3 cannot hold 9.- Because row 5 already has a 9, R5C1 and R5C3 cannot hold 9.- Because column 1 already has a 9, R6C1 cannot hold 9.- Because column 3 already has a 9, R6C3 cannot hold 9.So 9 must go in R6C2.
  5. R6C3 = 7 · Hidden SingleIn the middle-left 3×3 box, 7 fits in only one cell. Looking at the other empty cells:- Because row 4 already has a 7, R4C1, R4C2 and R4C3 cannot hold 7.- Because row 5 already has a 7, R5C1 and R5C3 cannot hold 7.- Because column 1 already has a 7, R6C1 cannot hold 7.So 7 must go in R6C3.
  6. R5C5 = 1 · Hidden SingleIn the centre 3×3 box, 1 fits in only one cell. Looking at the other empty cells:- Because column 4 already has a 1, R4C4 and R5C4 cannot hold 1.- Because column 6 already has a 1, R5C6 and R6C6 cannot hold 1.So 1 must go in R5C5.
  7. R4C3 = 1 · Hidden SingleIn the middle-left 3×3 box, 1 fits in only one cell. Looking at the other empty cells:- Because column 1 already has a 1, R4C1 and R6C1 cannot hold 1.- Because column 2 already has a 1, R4C2 cannot hold 1.- Because row 5 already has a 1, R5C1 and R5C3 cannot hold 1.So 1 must go in R4C3.
  8. R6C7 = 1 · Hidden SingleIn the middle-right 3×3 box, 1 fits in only one cell. Looking at the other empty cells:- Because row 4 already has a 1, R4C8 cannot hold 1.- Because row 5 already has a 1, R5C9 cannot hold 1.- Because column 8 already has a 1, R6C8 cannot hold 1.So 1 must go in R6C7.
  9. R9C4 = 7 · Hidden SingleIn the bottom-centre 3×3 box, 7 fits in only one cell. Looking at the other empty cells:- Because row 7 already has a 7, R7C4, R7C5 and R7C6 cannot hold 7.- Because column 6 already has a 7, R8C6 and R9C6 cannot hold 7.- Because column 5 already has a 7, R9C5 cannot hold 7.So 7 must go in R9C4.
  10. R7C9 = 1 · Hidden SingleIn the bottom-right 3×3 box, 1 fits in only one cell. Looking at the other empty cells:- Because column 7 already has a 1, R7C7 cannot hold 1.- Because column 8 already has a 1, R7C8 cannot hold 1.- Because row 8 already has a 1, R8C7, R8C8 and R8C9 cannot hold 1.- Because row 9 already has a 1, R9C7 and R9C9 cannot hold 1.So 1 must go in R7C9.
  11. R3C5 = 5 · Naked SingleLooking at R3C5:- Row 3 already has 1, 4, 8 and 9 → ruled out.- Column 5 already has 2, 3, 6 and 7 → ruled out.So this cell can only be 5.
  12. R4C2 = 8 · Naked SingleLooking at R4C2:- Row 4 already has 1, 3, 6, 7 and 9 → ruled out.- Column 2 already has 2, 4 and 5 → ruled out.So this cell can only be 8.
  13. R7C3 = 8 · Hidden SingleIn the bottom-left 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because column 1 already has an 8, R8C1 cannot hold 8.- Because column 2 already has an 8, R8C2 cannot hold 8.So 8 must go in R7C3.
  14. R7C6 = 3 · Hidden SingleIn row 7, 3 fits in only one cell. Looking at the other empty cells:- Because column 4 already has a 3, R7C4 cannot hold 3.- Because column 5 already has a 3, R7C5 cannot hold 3.- Because the bottom-right 3×3 box already has a 3, R7C7 cannot hold 3.- Because column 8 already has a 3, R7C8 cannot hold 3.So 3 must go in R7C6.
  15. R7C4 = 6 · Hidden SingleIn row 7, 6 fits in only one cell. Looking at the other empty cells:- Because column 5 already has a 6, R7C5 cannot hold 6.- Because column 7 already has a 6, R7C7 cannot hold 6.- Because column 8 already has a 6, R7C8 cannot hold 6.So 6 must go in R7C4.
  16. R3C6 = 6 · Hidden SingleIn the top-centre 3×3 box, 6 fits in only one cell. Looking at the other empty cells:- Because column 4 already has a 6, R2C4 cannot hold 6.So 6 must go in R3C6.
  17. R2C4 = 2 · Naked SingleLooking at R2C4:- Row 2 already has 1, 3, 4 and 9 → ruled out.- Column 4 already has 6, 7 and 8 → ruled out.- The top-centre 3×3 box already has 5 → ruled out.So this cell can only be 2.
  18. R6C6 = 2 · Hidden SingleIn the centre 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because column 4 already has a 2, R4C4 cannot hold 2.- Because row 5 already has a 2, R5C4 and R5C6 cannot hold 2.So 2 must go in R6C6.
  19. R5C6 = 8 · Hidden SingleIn the centre 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because row 4 already has an 8, R4C4 cannot hold 8.- Because column 4 already has an 8, R5C4 cannot hold 8.So 8 must go in R5C6.
  20. R4C8 = 2 · Hidden SingleIn the middle-right 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because row 5 already has a 2, R5C9 cannot hold 2.- Because row 6 already has a 2, R6C8 cannot hold 2.So 2 must go in R4C8.
  21. R6C8 = 8 · Hidden SingleIn the middle-right 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because row 5 already has an 8, R5C9 cannot hold 8.So 8 must go in R6C8.
  22. R6C1 = 5 · Naked SingleLooking at R6C1:- Row 6 already has 1, 2, 3, 4, 6, 7, 8 and 9 → ruled out.So this cell can only be 5.
  23. R5C9 = 5 · Naked SingleLooking at R5C9:- Row 5 already has 1, 2, 7, 8 and 9 → ruled out.- Column 9 already has 3 and 4 → ruled out.- The middle-right 3×3 box already has 6 → ruled out.So this cell can only be 5.
  24. R2C9 = 8 · Hidden SingleIn the top-right 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because row 1 already has an 8, R1C7 and R1C9 cannot hold 8.- Because column 8 already has an 8, R2C8 cannot hold 8.- Because row 3 already has an 8, R3C7 and R3C9 cannot hold 8.So 8 must go in R2C9.
  25. R4C4 = 5 · Hidden SingleIn the centre 3×3 box, 5 fits in only one cell. Looking at the other empty cells:- Because row 5 already has a 5, R5C4 cannot hold 5.So 5 must go in R4C4.
  26. R4C1 = 4 · Naked SingleLooking at R4C1:- Row 4 already has 1, 2, 3, 5, 6, 7, 8 and 9 → ruled out.So this cell can only be 4.
  27. R5C4 = 4 · Naked SingleLooking at R5C4:- Row 5 already has 1, 2, 5, 7, 8 and 9 → ruled out.- Column 4 already has 3 and 6 → ruled out.So this cell can only be 4.
  28. R8C6 = 4 · Hidden SingleIn the bottom-centre 3×3 box, 4 fits in only one cell. Looking at the other empty cells:- Because column 5 already has a 4, R7C5 cannot hold 4.- Because row 9 already has a 4, R9C5 and R9C6 cannot hold 4.So 4 must go in R8C6.
  29. R9C6 = 5 · Naked SingleLooking at R9C6:- Row 9 already has 1, 2, 3, 4 and 7 → ruled out.- Column 6 already has 6, 8 and 9 → ruled out.So this cell can only be 5.
  30. R9C5 = 8 · Hidden SingleIn the bottom-centre 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because row 7 already has an 8, R7C5 cannot hold 8.So 8 must go in R9C5.
  31. R7C5 = 9 · Naked SingleLooking at R7C5:- Row 7 already has 1, 3, 5, 6, 7 and 8 → ruled out.- Column 5 already has 2 and 4 → ruled out.So this cell can only be 9.
  32. R7C7 = 2 · Hidden SingleIn the bottom-right 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because column 8 already has a 2, R7C8 cannot hold 2.- Because row 8 already has a 2, R8C7, R8C8 and R8C9 cannot hold 2.- Because row 9 already has a 2, R9C7 and R9C9 cannot hold 2.So 2 must go in R7C7.
  33. R7C8 = 4 · Naked SingleLooking at R7C8:- Row 7 already has 1, 2, 3, 5, 6, 7, 8 and 9 → ruled out.So this cell can only be 4.
  34. R3C9 = 2 · Hidden SingleIn the top-right 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because row 1 already has a 2, R1C7 and R1C9 cannot hold 2.- Because row 2 already has a 2, R2C8 cannot hold 2.- Because column 7 already has a 2, R3C7 cannot hold 2.So 2 must go in R3C9.
  35. R2C8 = 7 · Hidden SingleIn the top-right 3×3 box, 7 fits in only one cell. Looking at the other empty cells:- Because row 1 already has a 7, R1C7 and R1C9 cannot hold 7.- Because column 7 already has a 7, R3C7 cannot hold 7.So 7 must go in R2C8.
  36. R8C8 = 5 · Naked SingleLooking at R8C8:- Row 8 already has 1, 2, 4 and 9 → ruled out.- Column 8 already has 3, 6, 7 and 8 → ruled out.So this cell can only be 5.
  37. R3C2 = 7 · Hidden SingleIn the top-left 3×3 box, 7 fits in only one cell. Looking at the other empty cells:- Because row 1 already has a 7, R1C3 cannot hold 7.- Because row 2 already has a 7, R2C2 and R2C3 cannot hold 7.So 7 must go in R3C2.
  38. R3C7 = 3 · Naked SingleLooking at R3C7:- Row 3 already has 1, 2, 4, 5, 6, 7, 8 and 9 → ruled out.So this cell can only be 3.
  39. R1C3 = 3 · Hidden SingleIn the top-left 3×3 box, 3 fits in only one cell. Looking at the other empty cells:- Because row 2 already has a 3, R2C2 and R2C3 cannot hold 3.So 3 must go in R1C3.
  40. R2C3 = 5 · Hidden SingleIn the top-left 3×3 box, 5 fits in only one cell. Looking at the other empty cells:- Because column 2 already has a 5, R2C2 cannot hold 5.So 5 must go in R2C3.
  41. R2C2 = 6 · Naked SingleLooking at R2C2:- Row 2 already has 1, 2, 3, 4, 5, 7, 8 and 9 → ruled out.So this cell can only be 6.
  42. R8C2 = 3 · Naked SingleLooking at R8C2:- Row 8 already has 1, 2, 4, 5 and 9 → ruled out.- Column 2 already has 6, 7 and 8 → ruled out.So this cell can only be 3.
  43. R5C3 = 6 · Naked SingleLooking at R5C3:- Row 5 already has 1, 2, 4, 5, 7, 8 and 9 → ruled out.- Column 3 already has 3 → ruled out.So this cell can only be 6.
  44. R5C1 = 3 · Naked SingleLooking at R5C1:- Row 5 already has 1, 2, 4, 5, 6, 7, 8 and 9 → ruled out.So this cell can only be 3.
  45. R8C1 = 6 · Naked SingleLooking at R8C1:- Row 8 already has 1, 2, 3, 4, 5 and 9 → ruled out.- Column 1 already has 7 and 8 → ruled out.So this cell can only be 6.
  46. R1C7 = 5 · Hidden SingleIn the top-right 3×3 box, 5 fits in only one cell. Looking at the other empty cells:- Because column 9 already has a 5, R1C9 cannot hold 5.So 5 must go in R1C7.
  47. R1C9 = 9 · Naked SingleLooking at R1C9:- Row 1 already has 1, 2, 3, 4, 5, 6, 7 and 8 → ruled out.So this cell can only be 9.
  48. R9C9 = 6 · Hidden SingleIn the bottom-right 3×3 box, 6 fits in only one cell. Looking at the other empty cells:- Because row 8 already has a 6, R8C7 and R8C9 cannot hold 6.- Because column 7 already has a 6, R9C7 cannot hold 6.So 6 must go in R9C9.
  49. R9C7 = 9 · Naked SingleLooking at R9C7:- Row 9 already has 1, 2, 3, 4, 5, 6, 7 and 8 → ruled out.So this cell can only be 9.
  50. R8C7 = 8 · Naked SingleLooking at R8C7:- Row 8 already has 1, 2, 3, 4, 5, 6 and 9 → ruled out.- Column 7 already has 7 → ruled out.So this cell can only be 8.
  51. R8C9 = 7 · Naked SingleLooking at R8C9:- Row 8 already has 1, 2, 3, 4, 5, 6, 8 and 9 → ruled out.So this cell can only be 7.

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