About YAOKU

YAOKU is a free, ad-free daily number puzzle operated by Elijah Maxwell. Its tagline says it all: where every number connects.

Lattice Sums

A YAOKU board is 6 × 6. Gray squares hold arrow clues that add along their groups; badges between neighbouring cells multiply; and the Loose Card tray holds exactly the digits the blank cells need, each used once. Read the full rules or take the tutorial.

How puzzles are made

Every Daily is generated and then certified before it is published: one program proves the solution is unique, and an independent program, written separately in another language, re-checks every sum, badge, and card and confirms the puzzle can be solved by logic alone. Answers are never sent to your browser with the puzzle.

Age and policies

YAOKU is for people age 13 and older. Read the Privacy Policy and Terms of Service, or get in touch.