Windoku. Hyper Sudoku.

Windoku is Hyper Sudoku — classic 9x9 Sudoku elevated by four shaded window regions that transform how you solve every puzzle. The four coloured windows are placed symmetrically inside the grid, each a 3x3 region that must also contain digits 1–9 without repetition. That gives you 13 constraint regions instead of the standard 9 — and it changes everything. Cells inside a window carry extra logical weight, the windows overlap with standard boxes and lines in ways that unlock powerful deductions, and the coloured grid is simply beautiful to look at. FOUR SHADED WINDOWS • 4 extra 3x3 regions placed symmetrically inside the grid • 13 total constraint regions — 9 standard plus 4 windows • Windows overlap rows, columns, and boxes — creating uniquely powerful logic • Also known as Hyper Sudoku, Window Sudoku, and NRC Sudoku SIX DIFFICULTY LEVELS • Easy: The windows guide you with extra constraints — perfect for newcomers • Medium: A satisfying daily challenge for regular solvers • Hard: Window logic becomes essential — not just helpful • Expert: Advanced techniques required across all 13 regions • Pro: Push your limits with multi-region elimination chains • Master: The ultimate test for dedicated puzzle solvers DAILY CHALLENGES • A fresh Windoku puzzle every single day • Build your streak and track progress on the calendar • Compete on global leaderboards and see how you rank worldwide TECHNIQUE LIBRARY • Learn the solving techniques that make window logic click • Interactive tutorials with real puzzle examples • Smart hints that explain the reasoning, not just the answer • Campaign mode with progressive levels from beginner to master ELEGANT DESIGN • Coloured windows make the grid immediately eye-catching • Clean, distraction-free interface lets you focus on solving • Twelve beautiful color themes with light and dark variants • Smooth animations and responsive native feel • Dark mode for comfortable late-night sessions SMART TOOLS • Pencil marks and inline candidates for noting possibilities • Unlimited undo and redo — experiment freely • Error highlighting to catch mistakes early • Auto-save so you never lose your progress • Highlight matching numbers to spot patterns instantly PLAY YOUR WAY • Works completely offline — play anywhere, anytime • No account required to start playing • Free to play with no paywalls blocking content • Cloud sync keeps your progress safe across devices Download free and discover what four extra windows can do. Terms of Use: https://www.locksmithcreativemilan.com/windoku/legal/terms-of-service.html