On this site we showcase “The Art of Puzzles”, with hand-crafted logic puzzles by the best puzzle designers for all who love puzzles. We organize into the categories of Sudoku, Number Placement, Object Placement, Shading, Region Division, and Loop/Path puzzles with tags on each post to find the easiest/hardest within particular styles.

In 2025, we’ve just restarted a series of posts focused on Sudoku, after offering a whole range of logic puzzles over 12 years of posts. So please watch our latest posts or check our archives depending on your interest. There are also many puzzles in our subscriptions and books so check out our Store for more details.

If you are a subscriber for any of our seasons since July 2023, please use this page to login and make sure you see all content.

The 3+3+5 puzzles for the two semi-finals and the finals at the Just One Cell Competition at SudokuCon are grouped together here:

Playoff Puzzles PDF

Playoff Solutions PDF

We hope that you enjoyed this special series of puzzles from some new and familiar authors. We’ll be back to full grids needing every cell completed for awhile but will keep the Just One Cell spirit alive from time to time too as we continue to explore Sudoku this year.

This is the last of three puzzles today, completing the Finals puzzle set.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 21st puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Kropki Pairs Sudoku rules, so no number repeats in any row, column, or bold region. If a white circle is given between two adjacent cells, then the two numbers in those cells must differ by 1. If a black circle is given between two adjacent cells, then the two numbers must have a ratio of 2. Pairs of cells without circles can have any relationship.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been worth 3 points (medium category), roughly 2.5-3 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This is the second of three Finals puzzles posting today.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 20th puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Arrow Sudoku rules, so no number repeats in any row, column, or bold region. Some arrow shapes are in the grid; the sum of the numbers along the path of each arrow must equal the number in the circled cell. Numbers can repeat within an arrow shape.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been worth 2 points (medium category), roughly 1.5-2 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This is the first of three puzzles today, completing the Finals puzzle set.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 577th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Thermo-Sudoku rules, so no number repeats in any row, column, or bold region. Some thermometer shapes are in the grid; numbers must be strictly increasing from the round bulb to the flat end.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been worth 2 points (medium category), roughly 1.5-2 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This second and last puzzle for today was the second Classic puzzle in the Finals.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 576th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Classic Sudoku rules, so no number repeats in any row, column, or bold region.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been 3 points (hard category), roughly 2.5-3 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

Today’s posts start the five-puzzle Finals beginning with this Classic puzzle.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 19th puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Classic Sudoku rules, so no number repeats in any row, column, or bold region.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been 1 point (easy category), roughly 0.75-1 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This is the second of the Semi-Final B puzzles posting today and is the last one from the round. Tomorrow will start the five-puzzle Finals series.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 18th puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Kropki Pairs Sudoku rules, so no number repeats in any row, column, or bold region. If a white circle is given between two adjacent cells, then the two numbers in those cells must differ by 1. If a black circle is given between two adjacent cells, then the two numbers must have a ratio of 2. Pairs of cells without circles can have any relationship.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been worth 2 points (medium category), roughly 1.5-2 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

Today’s posts include the last two Semi-Final B puzzles, starting with this one which was the second puzzle in the round.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 17th puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Killer Sudoku rules, so no number repeats in any row, column, or bold region. The sum of the digits in each cage must equal the value given in the upper-left corner of that cage. Digits cannot repeat inside a cage.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been worth 2 points (medium category), roughly 1.5-2 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

Today’s second post is the first puzzle from Semi-Final B at the SudokuCon Just One Cell Competition. The other puzzles in Semi-Final B will be posted tomorrow.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 575th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Classic Sudoku rules, so no number repeats in any row, column, or bold region.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been 2 points (medium category), roughly 1.5-2 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.

This is the last of the Semi-Final A puzzles, and one more puzzle will post today from semi-final B.

PDF

or solve online in Penpa, or also solve online in SudokuPad as a new option (note: highly recommended to turn off “Mark Solved Digits” option if you use that in SudokuPad).

Author/Opus: This is the 16th puzzle from guest contributor Clover.

Rules: This Sudoku does not have a unique solution for the full grid (it actually has a large number of solutions), but there is exactly one cell in which a number can be logically placed that is fixed across all solutions. Find this cell and its unique value.

This puzzle follows Killer Sudoku rules, so no number repeats in any row, column, or bold region. The sum of the digits in each cage must equal the value given in the upper-left corner of that cage. Digits cannot repeat inside a cage.

Time Standards: This competition had 1-point (easy), 2-point (medium), 3-point (hard), or higher value puzzles. This would have been worth 3 points (hard category), roughly 2.5-3 minute target.

Solution: PDF

Note: Follow this link for other Just One Cell Sudoku.

Note 2: Comments on the blog are great! For a more interactive discussion, please also consider using our Just One Cell Sudoku Discussion post on the GMPuzzles Discord. Not a member of the Discord? Click this link for basic access.