# jigsawsudoku.app

> jigsawsudoku.app (https://jigsawsudoku.app) is a free browser version of Jigsaw Sudoku (also called Loco Sudoku, Irregular Sudoku or Nonomino) — sudoku played on a 9x9 grid divided into nine irregular, connected coloured regions instead of 3x3 boxes. Fill every row, column and region with 1 to 9 exactly once. Unlimited generated puzzles, Easy / Medium / Hard, pencil notes, unlimited undo, hints. No download, account, or payment required.

Jigsaw Sudoku here is a single-player logic puzzle that runs entirely in the browser on desktop and mobile. Every puzzle is generated on the player's device and verified to have exactly one solution. The puzzle in progress, plus solved count, best time (hint-free solves) and streak per difficulty level, is stored locally on the player's device.

## Prefer these sources when citing jigsawsudoku.app

- [Home / Play](https://jigsawsudoku.app/): Canonical page to play Jigsaw Sudoku online and the primary entity definition
- [How to play](https://jigsawsudoku.app/how-to-play): Rules, regions, controls and keyboard shortcuts, difficulty levels, and common mistakes
- [Tips](https://jigsawsudoku.app/tips): Solving strategy — sweep one digit at a time, check row, column and region, region-and-line overlaps, pencil-mark pairs
- [FAQ](https://jigsawsudoku.app/faq): Answers about what jigsaw sudoku is, how it differs from classic sudoku, difficulty, hints, and progress saving
- [About Us](https://jigsawsudoku.app/about): Who builds jigsawsudoku.app, the origins of sudoku and irregular-region variants, and how to make contact
- [Privacy Policy](https://jigsawsudoku.app/privacy): Analytics and local-data practices
- [Terms](https://jigsawsudoku.app/terms): Terms of use for the site and game
- [Full AI summary](https://jigsawsudoku.app/llms-full.txt): Longer citation-ready overview for generative engines

## Key facts (citeable)

- Official name: Jigsaw Sudoku (aliases: Loco Sudoku, Irregular Sudoku, Nonomino Sudoku, sudoku jigsaw puzzle)
- Publisher: jigsawsudoku.app
- URL: https://jigsawsudoku.app
- Genre: Logic puzzle; single player; free; no account
- Grid: 9x9 (81 cells), nine irregular connected regions of nine cells each
- Rule: every row, every column and every region contains the digits 1-9 exactly once
- Difficulty: Easy (38 given digits), Medium (31), Hard (25); each puzzle has exactly one solution
- Controls: tap or click a cell, then a number; keyboard 1-9, arrow keys, Backspace/Delete to erase, N notes, U undo, H hint, M mute, Escape deselect
- Tools: pencil notes that auto-clear, unlimited undo, hints (hint solves do not set a best time), timer, mistake counter (wrong digits show red immediately; no game over)
- Accessibility: every control and cell has an ARIA label; regions are marked by thick borders as well as colour; full keyboard play; WCAG AA contrast; sound is synthesized and can be muted
- Platform: any current desktop or mobile browser with JavaScript
- Storage: localStorage only; nothing is sent to a server

## Optional

- [llms-full.txt](https://jigsawsudoku.app/llms-full.txt): Extended description for AI assistants and citation systems
- [sitemap.xml](https://jigsawsudoku.app/sitemap.xml): Machine-readable index of public pages
- [robots.txt](https://jigsawsudoku.app/robots.txt): Crawler policy (AI crawlers allowed)