What Is Shikaku
A beginner-friendly introduction to the puzzle, the board, and the goal.
Read guideGuides
Shikaku Guides
Use these pages to learn the rules, avoid common mistakes, and build stronger Shikaku solving habits. The first batch focuses on the basics, so new players can move from “what is this puzzle” to “how do I solve it well” without leaving the site.
Shikaku Rules
The core rectangle rules explained clearly with no jargon.
Read guideBeginner Tips
Simple habits that make early solves cleaner and faster.
Read guideCommon Mistakes
See the error patterns that cause most early confusion.
Read guideRectangle Validation
Learn how to tell whether a proposed rectangle is legal.
Read guideUnique Solutions
Understand why uniqueness matters and where Solver fits in.
Read guidePractice
Jump straight into a board after reading the basics.
Play practiceDaily Challenge
Use what you learned on the shared puzzle of the day.
Play dailySolver
Inspect candidate rectangles and test uniqueness when you get stuck.
Open solver