Stopple

The clock keeps running while this is open.

The daily puzzle

One puzzle a day, the same for everyone in the world. A new one appears at 00:00 UTC. Each puzzle has 3 letters and 4 categories, so 12 boxes. Fill every box with an answer from that box's category that starts with that box's letter, and finish as fast as you can.

The clock

The clock starts when the puzzle opens and can't be paused. Our server keeps the time, not your device, so closing the page or refreshing doesn't stop it. You can come back and carry on until the puzzle resets at 00:00 UTC; after that an unfinished puzzle counts as “Did not finish” (no ranking, no answers shown, no replay; your friends see “Did not finish” next to your name on the leaderboard). Your time is taken when every answer is correct and you submit.

What counts as correct

• The answer must belong to the category and start with the box's letter.
• Spelling must be exact. Capitals, accents, spaces, hyphens and punctuation don't matter, and a leading "The" is ignored.
• The game has its own keyboard on screen, with a space key for answers like "New York". There are no accent keys: type Turkiye or Sao Tome. On a computer you can use your own keyboard.
• Well-known alternative names and spellings are accepted (Burma or Myanmar, Türkiye or Turkey). Misspellings are not.
• Every box has at least one valid answer, so no puzzle is impossible. A few letters are deliberately hard, and no puzzle has more than 2 of them.

The categories

• Countries: the 193 UN member states plus the 2 UN observer states, the Holy See and the State of Palestine. Territories, UK nations such as Scotland, and partially recognised states don't count.
• Capital cities: the official capital of each of those countries, plus any city that is the seat of its government, legislature or highest court.
• Major cities: cities of 1 million or more people in the UN's 2025 data, using English names. Well-known variants such as Bombay and Peking are accepted. A few famous cities fall below 1 million in the UN's figures, such as Atlanta and Detroit, and don't count.
• Rivers: rivers of 1,000 km or longer, plus any river that flows through the capital city of one of those countries (for example the Seine, Thames and Tiber).
• Islands: an island counts if any one of these is true:
  • it is 1,000 km² or larger;
  • it is the whole of a UN member or observer state;
  • it holds the capital city of one;
  • more than 1 million people live on it;
  • it is named in a state's official name (Tobago, Nevis, Barbuda, Príncipe).
• Mammals: any living mammal by its common name (Quokka, Grey wolf), well-known group names such as bear, whale or bat, and domestic animals such as dog, cat, cow and horse. Extinct animals such as the mammoth don't count, and neither do plurals or baby and male/female names such as lamb or mare.
• Birds: any living bird by its common name (Barn Swallow, Quetzal) and well-known group names such as owl, eagle or duck. Extinct birds such as the dodo don't count, and neither do plurals.

Lifelines

You get three, and each works once per puzzle. Hint gives a clue for one box you choose. Change letter swaps one box's letter for the puzzle's spare letter, which works in every category. Answer fills in one well-known answer for a box you choose and keeps it there, so a box that has its Answer can't also be hinted or changed. Tap a lifeline, then tap the box; tap the lifeline again to cancel. They are free for everyone, cost no time, and aren't shown on leaderboards.

Revealing the answers

If you're stuck, open the menu (top right), choose Reveal answers and confirm. The clock stops and each empty or wrong box shows one example answer, drawn with a dashed edge. Boxes you answered correctly stay as you typed them. You won't be ranked that day, and you can't play that puzzle again. Revealing is final, so it works differently from the lifelines. Your friends can see that you revealed, but not your answers.

Leaderboard

The leaderboard shows you and your friends, ranked by time. To be ranked, sign in with Google or an email link and choose a username. Add friends with an invite link from the menu. Guests can play but aren't ranked. Times that look humanly impossible are removed from the board.

Everyone's numbers

After you finish, you see how long the day's puzzle took on average, your percentile (80th means you were faster than 80% of the players who finished), and how many people played. The average and percentile use valid timed finishes only; revealed, unfinished and removed times are left out. The numbers appear once enough people have finished.

Friends who revealed the answers (right away) or didn't finish (after the puzzle resets) are listed below the timed results, with no time or rank. Use the arrows to look at yesterday's board.

Guests and signing in

If you play as a guest and then sign in with a new account, you keep your result. If you sign in to an account that already exists, the game counts today's puzzle as already played on this device. It shows the result you got as a guest (unranked), and you can't play it again that day.

Data sources

• Major cities: United Nations, Department of Economic and Social Affairs, Population Division, World Urbanization Prospects 2025 (source), licensed under CC BY 3.0 IGO. We adapted the list (English names, alternative names).
• Rivers and islands: adapted from Wikipedia's List of river systems by length, List of islands by area and List of islands by population, licensed under CC BY-SA 4.0. We added some islands and rivers ourselves under the rules above.
• Mammals: adapted from the Mammal Diversity Database (American Society of Mammalogists), version 2.5, licensed under CC BY 4.0. We adapted the list (common names, group names, domestic animals, alternative spellings).
• Birds: adapted from the IOC World Bird List v15.2 (Gill, Donsker and Rasmussen, eds, 2026), doi 10.14344/IOC.ML.15.2, shared under a Creative Commons Attribution (CC BY) licence. We adapted the list (common names, group names, alternative spellings).
• Typeface: IBM Plex Sans, SIL Open Font License 1.1.