Murder Sudoku 3D Who's the killer?
A murder mystery you solve with pure logic. Place the suspects on the floor plan, follow their clues, and unmask the killer. Play free online in your browser, with no sign-up and no ads.
- Endless cases
- 3 difficulty levels
- 6 settings
- Phone, tablet, and computer
Sudoku meets a murder mystery
Every case is a floor plan with rooms, furniture, a victim, and a handful of suspects. Each suspect has one clue. Together, the clues lead to exactly one solution.
Read the case file
Each suspect has a clue, like "was next to the chest" or "was alone in the kitchen."
Put everyone in their place
Place the pawns on the board. Take notes and cross out squares, as in sudoku.
Accuse the killer
Who was alone with the victim? Name the killer and close the case.
The rules
- Each person is in their own row and their own column.
- People stand on an empty tile or on something you can sit, stand, or lie on, like a chair, bench, or bed.
- Next to means directly in front, behind, left, or right, in the same area. Walls separate the areas.
- Alone means nobody else is in the same area.
- The victim was alone with the killer.
Choose your level
- Easy: 6×6 with generous clues. A great place to start.
- Medium: 8×8, a solid puzzle to go with your coffee.
- Hard: 9×9, where every clue counts.
Stuck? The hint first points you in the right direction and only places a pawn on the second tap.
Choose your crime scene
The puzzle stays the same, the world changes. Each setting has its own rooms, furniture, suspects, and a living scene with light, shadow, and movement.
🏰 Castle
The court wanted a feast. It got a corpse.
🚀 Space
In space, no one can hear you scream. Except tonight.
🏴☠️ Pirates
The treasure is still here. The captain isn't.
🐫 Temple
The sun burns. The pharaoh keeps quiet. Someone is lying.
🌸 Teahouse
The tea was still warm. The host wasn't.
🏔️ Ski lodge
The blizzard closed the pass. Nobody could leave.
A new whodunit whenever you want
Endless cases
Every case is generated on the spot and has exactly one solution.
Share a case
Every case has a number. Send the link and play the same puzzle.
Notes
Small letters in the squares and crosses, like on paper.
Printable
Print a case on a single sheet, with the solution on a separate page.
Anywhere
Phone, tablet, or computer. Nothing to install.
Saves your progress
Stop halfway and pick up later on the same device.
No hassle
No sign-up, no ads, no tracking.
Open code
Free and open for noncommercial use. Anyone can help build it.
Questions about Murder Sudoku 3D
What is a murder sudoku?
A logic puzzle that combines sudoku with a murder mystery. You place the suspects and the victim on a floor plan divided into rooms. As in sudoku, each person has their own row and column. The clues tell you where everyone was, and the killer is the only person who was alone with the victim in a room.
Is Murder Sudoku 3D free?
Yes. It's completely free, with no ads, no sign-up, and no in-app purchases. The source code is on GitHub, free to use and change for noncommercial purposes.
Does it work on my phone or tablet?
Yes. Murder Sudoku 3D runs in the browser on phones, tablets, and computers. There's nothing to install, and your progress is saved on your own device.
Can I print the puzzles?
Yes. Open the classic version, choose a level, and tap Print. The solution goes on a separate page, so the printable puzzle works well for game nights and classrooms.
How many puzzles are there?
An endless supply. Every case is generated on the spot and checked for exactly one solution. Share the link to a case, and someone else plays the exact same puzzle.
How do I report a bug or share an idea?
Click Feedback, here or in the game from the three-dot menu. Your message opens as a prefilled form on GitHub, with the case number included. To submit it, you need a free GitHub account. After that, your message is public, so anyone can find the issue.
Help build Murder Sudoku 3D
Murder Sudoku 3D belongs to everyone. The code is on GitHub: anyone can play, study, change, and share it, as long as nobody makes money from it. You don't need to be an expert to contribute.
- Report a bug or idea with the Feedback button. That's already a contribution.
- Translate the game. Improve the English or Dutch text, or add a new language. Each language keeps all its text in one file.
- Design a new setting, like a circus, a train, or a haunted house. One file per setting, with a step-by-step guide.
- Work with an AI assistant. The repository includes instructions for Claude Code, Codex, Copilot, and other coding agents, plus automated tests that check your change.
git clone https://github.com/jeroenmarchand/murder-sudoku-3d
cd murder-sudoku-3d
npm install
npm run dev # open http://localhost:5173
npm test # checks that everything still worksRather not install anything? Open the repository in GitHub Codespaces, and everything is ready to go.