Yukti, a daily logic puzzle at playyukti.com, is made by Heet Mehta in India. Every day there is one puzzle, the same for everyone, generated and checked by code so that every move can be a certain deduction. It is free to play, needs no account, and keeps your progress in your own browser.
Why does Yukti exist?
Most daily games test what you already know. Most puzzle apps let you try every option until one works, or show you the answer when you get stuck. Yukti asks for something else: a move you can be sure of.
When you are stuck, a nudge asks you a question rather than telling you what to do. The puzzle is the same for everyone, so you can compare routes with friends without spoiling anything. And it is not a test: there are no grades, only the shortest route and how close you came.
How is each puzzle made?
A program builds each day's puzzle from the date. A solver then searches every possible move to prove the puzzle can be done, find its shortest route and set its level: Gentle early in the week, Steady midweek, Tough at the weekend.
The days are planned in advance and never change once played: the same date always gives the same puzzle, on every device. Nothing about the puzzle is written by hand, and nothing in it needs a guess.
Where do the puzzles come from?
Each kind of puzzle has a long history, and each one names its source on the page:
- Crossings: Problems to Sharpen the Young, attributed to Alcuin of York, about 800.
- Liars and truth-tellers: Raymond Smullyan's What Is the Name of This Book?, 1978.
- Logic grids: the Zebra Puzzle, 1962, and the Vetala Panchavimshati, tales of a king and a spirit, about the 11th century.
- Sound or fallacy: the Nyaya Sutras, India's classical logic, and their faulty reasons.
- The counting duel: Ashtavakra's duel of numbers with Bandi, in the Mahabharata.
- Anekanta, points of view: the blind men and the elephant, in the Buddhist Udana, and the Jain idea of anekantavada, many-sidedness.
The guides tell each story and show the method: Yukti's guides.
Does Yukti have videos?
Yes: Puzzles with a past, on YouTube. Short films about real events, from any era, with a puzzle inside. You get the same clues, solve it, then see how it was really solved. They never show today's puzzle.
Watch on YouTubeWhat does the name mean?
Yukti (say yook-tee) is Sanskrit for reasoning, method, the clever route to a solution.
How does Yukti pay for itself?
Ads, which are never personalised and never sit between the puzzle and its controls. Later, Yukti Plus for people who want more than one puzzle a day. The daily puzzle stays free.
What does Yukti keep about me?
Almost nothing. Your streak and results stay in your browser, and a solved puzzle sends one short anonymous note with no name and no ID. The Privacy page has the details.
How do I get in touch?
Write to hello@playyukti.com. Ideas for new kinds of puzzle are welcome.