About ThePuzzleLabs
Free puzzles that are checked before they reach you, plus three new dailies every morning.
What is here
The site has two halves. The Practice Library holds tens of thousands of ready-made puzzles across more than thirty types, including Sudoku and its variants, logic grids, Nonograms, Kakuro, cryptograms, anagrams and mazes. Each type carries five difficulty levels from Easy to Einstein, so you can pick a puzzle that matches how much thinking you feel like doing.
The Daily Experiment is the other half: a fresh set of puzzles every day, the same board for everyone, with difficulty that climbs from Monday to Sunday. Solving any one of them keeps your streak alive.
Why the puzzles are trustworthy
Every puzzle is produced by a generator program and then checked by a second, separate program that has to prove the puzzle has exactly one solution. A generator is never allowed to approve its own work, and puzzles that fail the check are discarded instead of published.
Einstein, the hardest level, carries a stricter promise: those puzzles are solvable by logic alone from beginning to end. If you are stuck on one, a deduction has been missed. You never need to guess. The full process is described in our editorial policy.
How it pays for itself
Advertising is what keeps the puzzles free to play. Ads are kept away from the board, and advertisers have no influence on which puzzles or articles get published. Signing in is optional and exists only to carry your streak and progress between devices.
Who runs it
ThePuzzleLabs is an independent project, founded and led by Arpit Verma, and played around the world. Bug reports and puzzle requests genuinely shape what gets built next, so if something looks wrong, please say so on the contact page. The people and projects behind the site are credited on the contributors page.