Sudoku World: Friend Challenge

Same Sudoku. Same rules. Challenge a friend, race their private ghost, and compare results—then build your Daily streak across Classic and Killer puzzles.

Same Sudoku. Same rules. Different solver.

Sudoku World turns a timeless logic puzzle into a fair friend challenge. Finish a board, share a link, and let a friend play the same Classic or Killer Sudoku on their schedule. Compare score, time, mistakes, and hints—no public profile required.

FRIEND CHALLENGES BUILT FOR REAL LIFE • Share one link; your friend has seven days to play • Choose whether teaching hints are allowed • Play with no mistake cap or a three-mistake limit • Compare both results under the same scoring rules • Rematch when you are ready

RACE A PRIVATE GHOST Turn on Ghost Race to see the challenger’s recorded pace move across the board. It shares cell locations and timing only—never entered numbers or private notes. The final result stays hidden until the puzzle is finished.

DAILY PUZZLES AND WORLD JOURNEY Build a Daily streak with fresh Classic and Killer boards, or catch up on the previous six days. First wins earn Journey points that unlock eight destination-inspired themes. On iOS, compare World Journey Points and unlock milestones through Game Center.

12,000+ INCLUDED PUZZLES Choose Fast, Easy, Medium, Hard, or Expert Classic Sudoku, plus Killer Sudoku from Easy through Expert. Included boards remain available offline; friend challenges, sync, and Journey awards require a connection.

TOOLS THAT HELP YOU LEARN • Pencil notes, unlimited undo, and auto-save • Teaching hints that explain the next logical step • Optional auto-check and duplicate highlighting • Light, dark, high-contrast, and large-control modes • Personal statistics, best times, and progress

BUILT FOR FOCUS Play as a guest, or use Sign in with Apple to sync supported progress. No full-screen ad appears while a puzzle is in progress. If you choose to delete your account, you can do it directly from Settings and start fresh.

Whether you are protecting a Daily streak, learning a new technique, or settling a friendly rematch, Sudoku World gives every solve somewhere to go.