Challenging Puzzle stumps Players Despite simple Appearance
A deceptively simple geometric puzzle, known as teh T-puzzle, is gaining renewed attention online after being featured by The Guardian. The puzzle, consisting of just four pieces, challenges players to form a perfect square – a task many find surprisingly tough despite its straightforward appearance.
Originally popular in the 19th century, the T-puzzle circulated widely as both a giveaway and a commercial wooden toy. A 1997 academic study revealed the puzzle’s difficulty: of five undergraduates tested, the fastest solved it in 2 minutes and 20 seconds, while three required a hint to complete it within 15 minutes. Now, a game developer has created an interactive version, inviting the public to test their skills and contribute to a live data collection effort.
Players can access an interactive version of the puzzle, complete with a timer, at https://technosquirrel.itch.io/t-puzzle. A printable PDF version is also available at https://uploads.guim.co.uk/2025/09/12/T-Puzzle_(1).pdf.pdf). The Guardian will publish the results of the ongoing player data collection, along with the solution, at 5pm UK time today.Readers are encouraged to participate and share their times, but are asked to refrain from posting spoilers, instead limiting comments to sentences begining with the letter “T.”
The puzzle’s enduring appeal lies in its accessibility and the unexpected cognitive challenge it presents. It serves as a compelling example of how visual perception and spatial reasoning can be easily misled. The puzzle was designed by Phoebe Fletcher. Those interested in suggesting future puzzles can email bellospuzzle@gmail.com.
