Sudoku Codex

Sudoku reimagined as an editorial library: 8 hand-tuned variants, daily & weekly challenges, hints that teach real techniques. Calm. Offline. Premium unlocked.

Sudoku Codex is an editorial library of Sudoku — eight distinct variants, four difficulty tiers, and a calm interface that respects your focus. Built for solvers who want depth instead of noise.

Most Sudoku apps give you one grid and a million popups. This one is different: a curated collection where Classic 9×9 sits beside Killer, Jigsaw, Hyper, Diagonal, Giant 16×16, Mini, and Color — every variant hand-tuned, every hint built to teach you, not just answer for you.

— THE CODEX: 8 VARIANTS, ONE LIBRARY —

• Classic 9×9 — The timeless grid, refined. Four difficulties: Easy, Medium, Hard, Expert. • Mini — Fast 4×4 and 6×6 grids. A quiet five-minute brain warm-up. • Diagonal — Both diagonals also hold 1–9. Adds a new layer of constraint. • Giant — Massive 12×12 and 16×16 grids for marathon sessions. • Killer — Sum-based cages add light arithmetic to pure logic. • Hyper — Four extra highlighted regions to deepen the puzzle. • Jigsaw (Irregular) — Curved, puzzle-shaped regions instead of 3×3 boxes. • Color — Visual variant with colors instead of digits. Beautiful and surprisingly hard.

— FIVE WAYS TO PLAY —

• Daily Challenge — One fresh puzzle, every day. Build streaks. Earn rewards. Never repeat. • Weekly Challenge — One global puzzle. Same board for every player worldwide. See exactly where you rank. • Time Attack — Race the clock. Beat your personal best. Climb global leaderboards. • Endless Mode — Unlimited generated puzzles across every variant and difficulty. • Puzzle Packs — Curated themed collections, each with a hand-picked difficulty arc.

— HINTS THAT TEACH —

Most Sudoku apps reveal the next correct number. We don't. Sudoku Codex shows you the technique — Naked Pair, Hidden Single, Pointing Pair, X-Wing, Swordfish — step by step, with the cells highlighted, so you actually learn the move. A built-in Techniques Library lets you study any tactic outside a game, with worked examples and practice grids.

— A QUIET INTERFACE —

We designed the board the way a typographer designs a page: generous whitespace, careful contrast, restrained color. No popups. No interruptions. No flashing badges screaming for attention. Just you, the grid, and your next move. Light and dark themes are both crafted, not auto-generated.

— OFFLINE, ALWAYS —

Every variant, every difficulty, every mode works without an internet connection. Play on the plane, on the subway, in a tunnel, in a waiting room. Progress auto-saves across the whole library.

— FOR EVERY KIND OF SOLVER —

• Daily commuters who want ten quiet, focused minutes • Lifelong fans ready to graduate from Classic to Killer or Jigsaw • Beginners learning the logic instead of guessing • Seniors and students keeping their minds sharp • Math, logic, and puzzle lovers of every level • Anyone tired of garish, ad-stuffed Sudoku apps

— WHAT MAKES THE CODEX DIFFERENT —

Eight variants curated like chapters, not bolted on as gimmicks. Hints that build skill instead of dependence. A Techniques Library that turns the app into a teacher. Statistics that follow your real growth across every variant, every difficulty, every mode. A daily ritual that respects your time.

This is Sudoku as a library, not a slot machine. A calm, durable companion for the long game.

— PREMIUM, UNLOCKED —

Every variant, every puzzle pack, every theme, every advanced hint — all unlocked. No paywalls between you and the next puzzle.

— LEGAL — Terms of Use: https://web-levi.web.app/terms-of-use Privacy Policy: https://web-levi.web.app/privacy-policy

— SUPPORT — Questions, feedback, or technique requests? tphuc.work@gmail.com

Open the Codex. Start your daily streak today.