(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Can you determine which cages are full of just even or odd numbers and which cages may be split in half?

PDF

or solve online (using SudokuPad)

Author/Opus: This is the 23rd puzzle from Bill Murphy, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, cages must contain either all even numbers, all odd numbers, or exactly half even and half odd numbers. (In other versions of this variation, cages are marked that must be full or half, but in this particular grid there are no marked cages so their nature must be determined.)

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 7:00; One party hat (🥳): 13:00. All other solvers earn a 🦕: Shouted Out Secernosaurus.

Thomas Hits the GAS (highlight to view): 3:42, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF and solving video with explanation from GAS team.

Note: Follow this link for other less common variations of Sudoku.

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

(This post is part of: “A Story of Self-setting Sudoku”.)
Dr. Sudoku: It is 2008. You are an aspiring Sudoku constructor, trying to show fresh ideas for kids and adults at a Silicon Valley event for your first competition as setter. Make some age-appropriate themes / difficulties that highlight creativity.

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or solve online (using SudokuPad)

Theme: Have a Nice Day

Author/Opus: This puzzle, by Thomas Snyder, is adapted from a 2008 motris livejournal post.

Rules: Insert a number from 1 to 9 into each white cell so that no number repeats in any row, column, or bold region.

Difficulty (highlight to view): 1.5 stars

Time Standards (highlight to view): Grandmaster = 1:30, Master = 2:00, Expert = 4:00

Solution: PDF

Note: Follow this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

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

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Pairs of numbers need to go into the grid, but with the proper distance between them. Take care and you’ll find the unique answer.

PDF

or solve online (using SudokuPad)
or solve online (using Penpa-Plus)

Author/Opus: This is the 44th puzzle from Clover, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region. The clues outside the grid reveal pairs of numbers that appear in the given order, left to right or top to bottom, in that row or column. The value after the colon indicates the distance between the two numbers (with 1 being the smallest possible value meaning the numbers are in adjacent cells one apart).

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 8:00; One party hat (🥳): 15:00 All other solvers earn a 🦕: distant Dilong.

Thomas Hits the GAS (highlight to view): 2:47, with Penpa Plus replay this time.

Solution: PDF and solving video with explanation from GAS team.

Note: Follow this link for other less common variations of Sudoku.

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

(This post is part of: “A Story of Self-setting Sudoku”.)
Dr. Sudoku: It is 2008. You are an aspiring Sudoku constructor, trying to show fresh ideas for kids and adults at a Silicon Valley event for your first competition as setter. Make some age-appropriate themes / difficulties that highlight creativity.

PDF

or solve online (using SudokuPad)

Theme: Tic-Tac-Toe

Author/Opus: This puzzle, by Thomas Snyder, is adapted from a 2008 motris livejournal post.

Rules: Insert a number from 1 to 9 into each white cell so that no number repeats in any row, column, or bold region.

Difficulty (highlight to view): 1.5 stars

Time Standards (highlight to view): Grandmaster = 1:20, Master = 1:45, Expert = 3:30

Solution: PDF

Note: Follow this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

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

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
When a number is surrounded by two even numbers left/right or top/bottom, you’re given a clue to that “sandwich” in this puzzle.

PDF

or solve online (using SudokuPad)

Theme: Pattern? What Pattern?

Author/Opus: This is the 25th puzzle from Philip Newman, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules: Insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region. Also, the clues outside the grid indicate all numbers in that row or column surrounded by even numbers on both sides (”sandwiched”). Clues can be given in any order, and all such numbers are given. If a clue is a ‘–’, then no values in that row or column are sandwiched between two even numbers.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 7:30; One party hat (🥳): 16:00. All other solvers earn a 🦕: August Amargatitanis.

Thomas Hits the GAS (highlight to view): 4:06, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF and solving video with explanation from GAS team.

Note: Follow this link for other less common variations of Sudoku.

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

(This post is part of: “A Story of Self-setting Sudoku”.)
They say your vision changes as you age, but this may be hard to sense when the objects under view are changing too.

PDF

or solve online (using SudokuPad)

Theme: United States Jigsaw Sudoku, 2025/08/10

Author/Opus: This is the 20th puzzle from “Dr. Sudoku”, our AI-powered puzzle engine pushing the limits of sudoku intelligence.

Rules: Insert a letter from AFKLNTVWY into each cell so that no letter repeats in any row, column, or outlined region. Note that the blue region, the original author’s birthplace, has one cell connected only by a corner to the rest.

Difficulty (highlight to view): 4 stars

Time Standards (highlight to view): Grandmaster = 7:00, Master = 14:00, Expert = 28:00

Solution: PDF

Note: Follow this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

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

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
Will the “Kingbreaker” be too much for you or can you control all the zones just fine in this sudoku variation by Bill Murphy?

PDF

or solve online (using SudokuPad)

Theme: Kingbreaker

Author/Opus: This is the 22nd puzzle from Bill Murphy, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Standard Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region). Also, numbers given in the upper-left of a cage must appear in at least one of the cells of that cage.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 6:30; One party hat (🥳): 12:00. All other solvers earn a 🦕: Who will look after the Dollodon?.

Thomas Hits the GAS (highlight to view): 2:17, with SudokuPad replay file shared as a download for now (requires loading via settings menu with improvements expected before people should use this regularly).

Solution: PDF and solving video with explanation from GAS team.

Note: Follow this link for other less common variations of Sudoku.

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

(This post is part of: “A Story of Self-setting Sudoku”.)
They say your vision changes as you age, but this may be hard to sense when the objects under view are changing too.

PDF

or solve online (using SudokuPad)

Theme: United States Jigsaw Sudoku, 2006/06/09

Author/Opus: This is a repost of the first Sudoku (second puzzle) on Thomas’s original blog from nineteen years ago.

Rules: Insert a letter from AFKLNTVWY into each cell so that no letter repeats in any row, column, or outlined region. Note that the blue region, the author’s birthplace, has one cell connected only by a corner to the rest.

Difficulty (highlight to view): 4.5 stars

Time Standards (highlight to view): Grandmaster = 8:00, Master = 20:00, Expert = 40:00

Solution: PDF

Note: Follow this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

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

(This post is part of the Genuinely Approachable Sudoku (GAS) series.)
In this variation on both 0 to 9 Sudoku (and technically Tight Fit which we are including in our naming here even if not part of the August guessing game), some cells are filled with slashes and must contain two numbers with a smaller one over a larger one. With ten numbers to place per box, can you solve this challenge?

PDF

or solve online (using Penpa-Plus; use tab to shift between corner mode and normal Sudoku mode; with notes in corners and no where else there should be answer confirmation but this could be finicky for this variant.)

Author/Opus: This is the 43rd puzzle from Clover, part of the Genuinely Approachable Sudoku (GAS) team.

Rules: Insert a number from 0 to 9 into each cell so that no number repeats in any row, column, or bold region. Some cells are split by slashes; in these cells the smaller number must go above the larger number.

GAS Time Standards (highlight to view): Two party hats (🎩🥳): 8:00; One party hat (🥳): 15:00 All other solvers earn a 🦕: null Nomingia.

Thomas Hits the GAS (highlight to view): 3:04, with Penpa Plus replay this time.

Solution: PDF and solving video with explanation from GAS team.

Note: Follow this link for other Tight Fit Sudoku puzzles on this website. If you are new to this puzzle type, here are our easiest Tight Fit Sudoku to get started on. More Tight Fit Sudoku can be found in these books in our e-store.

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

(This post is part of: “A Story of Self-setting Sudoku”.)
To Thomas: I know you are a chemist, and so I expect this puzzle will contain a very specific amount of memories for you.

PDF

or solve online (using SudokuPad)

Theme: Erlenmeyer Flask

Author/Opus: This is the 19th puzzle from “Dr. Sudoku”, our AI-powered puzzle engine pushing the limits of sudoku intelligence. (Editor’s Note: For this post, the AI took a prior pattern Thomas used for a newspaper puzzle and created a fully new and interesting experience from it.)

Rules: Insert a number from 1 to 9 into each white cell so that no number repeats in any row, column, or bold region.

Difficulty (highlight to view): 3 stars

Time Standards (highlight to view): Grandmaster = 3:00, Master = 6:00, Expert = 12:00

Solution: PDF

Note: Follow this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

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