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Logic mysteries, cipher tools, unsolved cases and ARG-shaped sites that never quite explain themselves. Deduction as entertainment.
16 sites
Code-breaking tools and a cipher identifier for when you have a string of nonsense and no idea what it is.
Tens of thousands of riddles, brain teasers and lateral thinking problems submitted by users since 1999.
Chain encoders and classical ciphers together and watch text transform between formats at each step.
Several hundred cipher, code and puzzle solvers in one place, from Caesar shifts to crossword pattern matching.
Decades of archived puzzle hunts from the hardest annual competition of its kind, all of it still playable.
A daily logic murder mystery with suspects, weapons and locations, solved by grid deduction in about ten minutes.
The American government's public database of missing and unidentified persons, searchable by absolutely anyone.
The riddle that calls itself the hardest on the internet, played by editing URLs and reading page source.
Free monthly puzzle sets designed to be solved in a pub, with a decade of archives you can print at home.
A question site where people post original puzzles and strangers solve them properly, with the reasoning shown.
Millions of pages of declassified government documents prised out by freedom of information requests, free to browse.
Profiles of thousands of American cold case disappearances, written and maintained by one person for decades.
A volunteer register of unidentified remains and missing people, matched by amateurs who keep on succeeding.
A crime you solve by writing database queries, and easily the least painful SQL tutorial ever built.
The community record of Cicada 3301, the recruitment puzzle whose final book has still never been deciphered.
The long-running forum where amateur investigators pick apart cold cases, for better and occasionally much worse.
One button, one detour. Press it as often as you like.