Help & questions

New here? The two-minute tutorial teaches every rule on a real board.

Playing

When do new puzzles appear?

Three Dailies (Easy, Medium, and Hard) start at midnight America/Chicago time, every day of the year, including across daylight-saving changes. Your device’s clock does not choose the puzzle; YAOKU’s server does, so everyone gets the same three boards.

What makes a puzzle Easy, Medium, or Hard?

Each puzzle is rated by the hardest logical step it needs. Easy puzzles fall to direct steps: the last cell of a group, a badge with one known side, or a card that has run out. Medium puzzles need you to list which digit combinations can reach a group’s total. Hard puzzles need card counting across several groups at once. The ratings are measured by a solver and are still being tuned with player feedback.

Can a puzzle have two answers? Do I ever have to guess?

No and no. Every Daily is checked by two independent programs before it is published: one proves there is exactly one solution, and another confirms that it can be solved step by step without guessing.

Can digits repeat?

Not inside one arrowed group. Anywhere else, yes: in another group, another row, or on either side of the centre square. The Loose Card tray often holds repeated numbers; each is its own card.

What are Check, Hint, and assists?

Check marks placed digits that do not match the solution. Hint points to the next logical step and names the rule, without saying the digit. Each use counts as an assist. Assists never block you from finishing; on leaderboards, fewer assists rank higher.

Saving and offline play

Guest progress is saved in this browser on this device and is not sent anywhere. Today’s Daily needs a connection to open, but once open it can be resumed offline until the next reset. YAOKU has only the Daily: there are no random or practice puzzles. You can install YAOKU from your browser’s menu (“Install app” or “Add to Home Screen”).

Accounts, official results, and leaderboards

Do I need an account?

No. Every puzzle is free to play as a guest. An account adds official, server-timed Daily results, leaderboards, and stats that follow you between devices.

How does an official Daily attempt work?

Choose “Play the official” Easy, Medium, or Hard on a Daily while signed in. It is the same puzzle every player gets that day. The server starts your timer, records each move, and recognises the finish itself, so times cannot be edited. An official attempt cannot be paused. You get one official result per puzzle. Finishing faster than one second per blank cell is not accepted.

How are leaderboards ordered?

Each Daily Leaderboard covers one Chicago date and one difficulty. It ranks fewer assists first, then fewer mistakes, then faster times, then the earlier finish. Boards for the last 30 Chicago days can be viewed.

How does the Weekly Leaderboard work?

Each Weekly Leaderboard covers one difficulty for one week, from Friday 00:00 to Thursday 23:59 UTC. The Daily itself still changes at midnight in Chicago; only the weekly grouping uses UTC dates. It counts one official Daily completion per UTC date: if you finish two official Dailies of the same difficulty on one UTC date (possible around the Chicago reset), the first one counts. Players are ranked by the most completions, then the lowest total server-measured time, then the fewest mistakes, then the fewest hints; players equal on all four share a rank. Everything is calculated by the server from official results. Earlier weeks stay viewable after Friday’s reset.

Passkeys

Why passkeys and no password?

A passkey is stored by your device or password manager and unlocked with your screen lock, fingerprint, or face. It cannot be phished or reused on another site, and YAOKU never sees a password. Accounts need only a username: no email address.

What if I lose my passkey?

There is no email or password recovery. Add a second passkey (another device or a security key) from Passkeys so you always have a way in. If every passkey is lost, the account cannot be recovered, but you can create a new one.

How do I sign out other devices or delete my account?

See Active sessions to sign out any device, and your profile to download your data or delete the account and all of its results.

Accessibility

The board works with a keyboard alone: arrow keys move between white cells, 1–9 places a card, Backspace clears, N toggles Notes, and Ctrl/⌘ Z undoes. Every cell, clue, badge, and card has a spoken label for screen readers. Settings offers dark mode, reduced motion, and live rule highlighting. If something does not work for you, please tell us.

Contact

Questions about playing: support@playyaoku.com. More addresses are on the contact page.