Matle

Matle builds its puzzles from finished games that ended in checkmate. The board shows the final position with several squares marked by question marks, and your job is to work out what stands on each of them: a white or black piece of a given type, or nothing at all.

You fill in the hidden squares from a palette of pieces and submit the guess. A green square means the right piece on the right square, yellow means that piece belongs on another hidden square, and grey means the piece is wrong. You have five guesses, a hint is available if you are stuck, and you can flip the board to Black's side. When you solve it, the game names the game it came from, such as a Tal or Carlsen win, with a link to the full score.

There is one daily puzzle for everyone, with community statistics on how others guessed. Its difficulty changes from day to day: the label beside the board reads Basic, Medium or Hard. A side menu also holds small puzzle collections, such as three Magnus Carlsen mates and three from Daniel Naroditsky's Titled Tuesday games. If you miss a day you can still play yesterday's puzzle to keep your streak. Play works without an account; optional Google sign-in syncs stats, streaks and achievements across devices, and players can submit their own checkmates.

It suits chess players who enjoy mating patterns and want a short daily puzzle that rewards knowing why a position is checkmate.