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Daily Sudoku — 18 July 2026

The puzzle

  • 18 July 2026
  • Hard
  • 30 clues
Puzzle
··1···6··
·79··6·14
·3··1·5·7
·6··7····
···5·21··
····4·97·
·95·64···
7·····462
4··1··3··
Solution
841795623
579326814
632418597
164879235
987532146
253641978
395264781
718953462
426187359

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. R5C3 = 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 and R4C3 cannot hold 7.- Because column 1 already has a 7, R5C1 cannot hold 7.- Because column 2 already has a 7, R5C2 cannot hold 7.- Because row 6 already has a 7, R6C1, R6C2 and R6C3 cannot hold 7.So 7 must go in R5C3.
  2. R6C4 = 6 · Hidden SingleIn the centre 3×3 box, 6 fits in only one cell. Looking at the other empty cells:- Because row 4 already has a 6, R4C4 and R4C6 cannot hold 6.- Because column 5 already has a 6, R5C5 cannot hold 6.- Because column 6 already has a 6, R6C6 cannot hold 6.So 6 must go in R6C4.
  3. R5C9 = 6 · Hidden SingleIn the middle-right 3×3 box, 6 fits in only one cell. Looking at the other empty cells:- Because row 4 already has a 6, R4C7, R4C8 and R4C9 cannot hold 6.- Because column 8 already has a 6, R5C8 cannot hold 6.- Because row 6 already has a 6, R6C9 cannot hold 6.So 6 must go in R5C9.
  4. R9C3 = 6 · Hidden SingleIn the bottom-left 3×3 box, 6 fits in only one cell. Looking at the other empty cells:- Because row 7 already has a 6, R7C1 cannot hold 6.- Because row 8 already has a 6, R8C2 and R8C3 cannot hold 6.- Because column 2 already has a 6, R9C2 cannot hold 6.So 6 must go in R9C3.
  5. R3C1 = 6 · Hidden SingleIn the top-left 3×3 box, 6 fits in only one cell. Looking at the other empty cells:- Because row 1 already has a 6, R1C1 and R1C2 cannot hold 6.- Because row 2 already has a 6, R2C1 cannot hold 6.- Because column 3 already has a 6, R3C3 cannot hold 6.So 6 must go in R3C1.
  6. 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 9 already has a 1, R9C8 and R9C9 cannot hold 1.So 1 must go in R7C9.
  7. R8C2 = 1 · Hidden SingleIn the bottom-left 3×3 box, 1 fits in only one cell. Looking at the other empty cells:- Because row 7 already has a 1, R7C1 cannot hold 1.- Because column 3 already has a 1, R8C3 cannot hold 1.- Because row 9 already has a 1, R9C2 cannot hold 1.So 1 must go in R8C2.
  8. R7C7 = 7 · Hidden SingleIn the bottom-right 3×3 box, 7 fits in only one cell. Looking at the other empty cells:- Because column 8 already has a 7, R7C8 and R9C8 cannot hold 7.- Because column 9 already has a 7, R9C9 cannot hold 7.So 7 must go in R7C7.
  9. R9C6 = 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 cannot hold 7.- Because row 8 already has a 7, R8C4, R8C5 and R8C6 cannot hold 7.- Because column 5 already has a 7, R9C5 cannot hold 7.So 7 must go in R9C6.
  10. R1C4 = 7 · Hidden SingleIn the top-centre 3×3 box, 7 fits in only one cell. Looking at the other empty cells:- Because column 5 already has a 7, R1C5 cannot hold 7.- Because column 6 already has a 7, R1C6 cannot hold 7.- Because row 2 already has a 7, R2C4 and R2C5 cannot hold 7.- Because row 3 already has a 7, R3C4 and R3C6 cannot hold 7.So 7 must go in R1C4.
  11. R3C4 = 4 · Hidden SingleIn the top-centre 3×3 box, 4 fits in only one cell. Looking at the other empty cells:- Because column 5 already has a 4, R1C5 cannot hold 4.- Because column 6 already has a 4, R1C6 and R3C6 cannot hold 4.- Because row 2 already has a 4, R2C4 and R2C5 cannot hold 4.So 4 must go in R3C4.
  12. R1C2 = 4 · Hidden SingleIn the top-left 3×3 box, 4 fits in only one cell. Looking at the other empty cells:- Because column 1 already has a 4, R1C1 cannot hold 4.- Because row 2 already has a 4, R2C1 cannot hold 4.- Because row 3 already has a 4, R3C3 cannot hold 4.So 4 must go in R1C2.
  13. R4C3 = 4 · Hidden SingleIn the middle-left 3×3 box, 4 fits in only one cell. Looking at the other empty cells:- Because column 1 already has a 4, R4C1 and R5C1 cannot hold 4.- Because column 2 already has a 4, R5C2 cannot hold 4.- Because row 6 already has a 4, R6C1, R6C2 and R6C3 cannot hold 4.So 4 must go in R4C3.
  14. R5C8 = 4 · Hidden SingleIn the middle-right 3×3 box, 4 fits in only one cell. Looking at the other empty cells:- Because row 4 already has a 4, R4C7, R4C8 and R4C9 cannot hold 4.- Because row 6 already has a 4, R6C9 cannot hold 4.So 4 must go in R5C8.
  15. R6C2 = 5 · Hidden SingleIn column 2, 5 fits in only one cell. Looking at the other empty cells:- Because row 5 already has a 5, R5C2 cannot hold 5.- Because the bottom-left 3×3 box already has a 5, R9C2 cannot hold 5.So 5 must go in R6C2.
  16. R9C2 = 2 · Hidden SingleIn column 2, 2 fits in only one cell. Looking at the other empty cells:- Because row 5 already has a 2, R5C2 cannot hold 2.So 2 must go in R9C2.
  17. R5C2 = 8 · Naked SingleLooking at R5C2:- Row 5 already has 1, 2, 4, 5, 6 and 7 → ruled out.- Column 2 already has 3 and 9 → ruled out.So this cell can only be 8.
  18. R7C4 = 2 · Hidden SingleIn the bottom-centre 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because row 8 already has a 2, R8C4, R8C5 and R8C6 cannot hold 2.- Because row 9 already has a 2, R9C5 cannot hold 2.So 2 must go in R7C4.
  19. R7C1 = 3 · Hidden SingleIn row 7, 3 fits in only one cell. Looking at the other empty cells:- Because the bottom-right 3×3 box already has a 3, R7C8 cannot hold 3.So 3 must go in R7C1.
  20. R7C8 = 8 · Naked SingleLooking at R7C8:- Row 7 already has 1, 2, 3, 4, 5, 6, 7 and 9 → ruled out.So this cell can only be 8.
  21. R8C3 = 8 · Naked SingleLooking at R8C3:- Row 8 already has 1, 2, 4, 6 and 7 → ruled out.- Column 3 already has 5 and 9 → ruled out.- The bottom-left 3×3 box already has 3 → ruled out.So this cell can only be 8.
  22. R6C3 = 3 · Hidden SingleIn the middle-left 3×3 box, 3 fits in only one cell. Looking at the other empty cells:- Because column 1 already has a 3, R4C1, R5C1 and R6C1 cannot hold 3.So 3 must go in R6C3.
  23. R3C3 = 2 · Naked SingleLooking at R3C3:- Row 3 already has 1, 3, 4, 5, 6 and 7 → ruled out.- Column 3 already has 8 and 9 → ruled out.So this cell can only be 2.
  24. R9C5 = 8 · Hidden SingleIn the bottom-centre 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because row 8 already has a 8, R8C4, R8C5 and R8C6 cannot hold 8.So 8 must go in R9C5.
  25. R3C6 = 8 · Hidden SingleIn row 3, 8 fits in only one cell. Looking at the other empty cells:- Because column 8 already has a 8, R3C8 cannot hold 8.So 8 must go in R3C6.
  26. R3C8 = 9 · Naked SingleLooking at R3C8:- Row 3 already has 1, 2, 3, 4, 5, 6, 7 and 8 → ruled out.So this cell can only be 9.
  27. R4C4 = 8 · Hidden SingleIn the centre 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because column 6 already has a 8, R4C6 and R6C6 cannot hold 8.- Because row 5 already has a 8, R5C5 cannot hold 8.So 8 must go in R4C4.
  28. R6C9 = 8 · Hidden SingleIn the middle-right 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because row 4 already has a 8, R4C7, R4C8 and R4C9 cannot hold 8.So 8 must go in R6C9.
  29. R2C7 = 8 · Hidden SingleIn the top-right 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because column 8 already has a 8, R1C8 cannot hold 8.- Because column 9 already has a 8, R1C9 cannot hold 8.So 8 must go in R2C7.
  30. R4C7 = 2 · Naked SingleLooking at R4C7:- Row 4 already has 4, 6, 7 and 8 → ruled out.- Column 7 already has 1, 3, 5 and 9 → ruled out.So this cell can only be 2.
  31. R1C1 = 8 · Hidden SingleIn the top-left 3×3 box, 8 fits in only one cell. Looking at the other empty cells:- Because row 2 already has a 8, R2C1 cannot hold 8.So 8 must go in R1C1.
  32. R2C1 = 5 · Naked SingleLooking at R2C1:- Row 2 already has 1, 4, 6, 7, 8 and 9 → ruled out.- Column 1 already has 3 → ruled out.- The top-left 3×3 box already has 2 → ruled out.So this cell can only be 5.
  33. R1C8 = 2 · Hidden SingleIn the top-right 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because column 9 already has a 2, R1C9 cannot hold 2.So 2 must go in R1C8.
  34. R1C9 = 3 · Naked SingleLooking at R1C9:- Row 1 already has 1, 2, 4, 6, 7 and 8 → ruled out.- The top-right 3×3 box already has 5 and 9 → ruled out.So this cell can only be 3.
  35. R2C5 = 2 · Hidden SingleIn the top-centre 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because row 1 already has a 2, R1C5 and R1C6 cannot hold 2.- Because column 4 already has a 2, R2C4 cannot hold 2.So 2 must go in R2C5.
  36. R2C4 = 3 · Naked SingleLooking at R2C4:- Row 2 already has 1, 2, 4, 5, 6, 7, 8 and 9 → ruled out.So this cell can only be 3.
  37. R8C4 = 9 · Naked SingleLooking at R8C4:- Row 8 already has 1, 2, 4, 6, 7 and 8 → ruled out.- Column 4 already has 3 and 5 → ruled out.So this cell can only be 9.
  38. R6C1 = 2 · Hidden SingleIn the middle-left 3×3 box, 2 fits in only one cell. Looking at the other empty cells:- Because row 4 already has a 2, R4C1 cannot hold 2.- Because row 5 already has a 2, R5C1 cannot hold 2.So 2 must go in R6C1.
  39. R6C6 = 1 · Naked SingleLooking at R6C6:- Row 6 already has 2, 3, 4, 5, 6, 7, 8 and 9 → ruled out.So this cell can only be 1.
  40. R4C1 = 1 · Hidden SingleIn the middle-left 3×3 box, 1 fits in only one cell. Looking at the other empty cells:- Because row 5 already has a 1, R5C1 cannot hold 1.So 1 must go in R4C1.
  41. R5C1 = 9 · Naked SingleLooking at R5C1:- Row 5 already has 1, 2, 4, 5, 6, 7 and 8 → ruled out.- Column 1 already has 3 → ruled out.So this cell can only be 9.
  42. R5C5 = 3 · Naked SingleLooking at R5C5:- Row 5 already has 1, 2, 4, 5, 6, 7, 8 and 9 → ruled out.So this cell can only be 3.
  43. R4C6 = 9 · Naked SingleLooking at R4C6:- Row 4 already has 1, 2, 4, 6, 7 and 8 → ruled out.- The centre 3×3 box already has 3 and 5 → ruled out.So this cell can only be 9.
  44. R1C5 = 9 · Hidden SingleIn the top-centre 3×3 box, 9 fits in only one cell. Looking at the other empty cells:- Because column 6 already has a 9, R1C6 cannot hold 9.So 9 must go in R1C5.
  45. R1C6 = 5 · Naked SingleLooking at R1C6:- Row 1 already has 1, 2, 3, 4, 6, 7, 8 and 9 → ruled out.So this cell can only be 5.
  46. R8C5 = 5 · Naked SingleLooking at R8C5:- Row 8 already has 1, 2, 4, 6, 7, 8 and 9 → ruled out.- Column 5 already has 3 → ruled out.So this cell can only be 5.
  47. R8C6 = 3 · Naked SingleLooking at R8C6:- Row 8 already has 1, 2, 4, 5, 6, 7, 8 and 9 → ruled out.So this cell can only be 3.
  48. R4C8 = 3 · Hidden SingleIn the middle-right 3×3 box, 3 fits in only one cell. Looking at the other empty cells:- Because column 9 already has a 3, R4C9 cannot hold 3.So 3 must go in R4C8.
  49. R4C9 = 5 · Naked SingleLooking at R4C9:- Row 4 already has 1, 2, 3, 4, 6, 7, 8 and 9 → ruled out.So this cell can only be 5.
  50. R9C8 = 5 · Naked SingleLooking at R9C8:- Row 9 already has 1, 2, 3, 4, 6, 7 and 8 → ruled out.- Column 8 already has 9 → ruled out.So this cell can only be 5.
  51. R9C9 = 9 · Naked SingleLooking at R9C9:- Row 9 already has 1, 2, 3, 4, 5, 6, 7 and 8 → ruled out.So this cell can only be 9.

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