Ninefold: Daily Variant Sudoku

A new sudoku variant every day, a 6×6 Sprint you can share, and a coach that names the technique behind every hint.

Ninefold Sudoku is the daily home for variant sudoku.

A NEW VARIANT EVERY DAY Monday Classic, Tuesday Killer, Wednesday Diagonal, Thursday Jigsaw, Friday Thermo, Saturday Sandwich, and a Sunday Duo that combines two rule sets. Every daily puzzle is hand-verified to have exactly one solution and to be solvable by pure logic — no guessing, ever.

THE 6×6 SPRINT A one-to-three-minute race with an accuracy grid you can share: green for first try, yellow for corrected. Compare times with friends and on Game Center.

A COACH THAT TEACHES The hint button never just gives you a digit. First a nudge ("Look at box 5"), then the name of the technique, then the deduction drawn on the board, and only then the digit. Twenty-four techniques, from naked singles to X-Wings, XY-Wings, cage combinations, the 45 rule, thermometer bounds and sandwich arrangements — each with a playable lesson and a mastery badge.

EVERY VARIANT, UNLIMITED Practice any variant at five grades, from Easy to Extreme, with thousands of verified puzzles and new ones generated as you play. Take on the weekly Variant Cup: seven puzzles, one score, one leaderboard.

MADE TO BE HELD Ink on warm paper, a board drawn like a printed puzzle magazine, digits that drop in with a soft ripple, calm sound and haptics designed together. Dark theme, four extra themes, full Dynamic Type and VoiceOver support, left-hand mode, and an iPad layout.

STREAKS AND STATS Separate streaks for the variant and the Sprint, Perfect Days, streak freezes, a calendar archive, per-variant stats, achievements and a trophy room. Widgets show today's variant and your streak.

FAIR BY DESIGN Ads appear only on the completion screen, never on the board. One purchase removes them for good. Hints are always available by choice.

Ninefold Premium (optional): no ads, unlimited hints, the full archive, every theme and advanced stats — $3.99/month or $19.99/year with a 3-day free trial. Payment is charged to your Apple ID; subscriptions renew automatically unless cancelled at least 24 hours before the end of the period. Privacy: https://ninefold-sudoku.pages.dev/privacy/ · Terms: https://ninefold-sudoku.pages.dev/terms/