Crack the Code (Puzzleship)

Crack the Code is Puzzleship's take on the classic lock riddle. Each clue pairs a code someone tried with a plain-language verdict: how many digits were right, and whether they sat in the right place. Some clues say nothing is correct, which rules those digits out entirely. All digits in a code are different, and only one code fits every clue.

Every day Puzzleship numbers a new set of six locks, picked by a row of light bulbs from one for very easy to six for ultra hard. The very easy lock of 19 Oct had three digits and four clues and took a minute or two; the higher levels are meant for pencil and paper. You type the answer into the boxes beside the padlock, and the game tells you straight away when the code opens it, with a streak counter for days in a row.

While you reason you can tap digits in the clues to mark them as not present, present somewhere, or fixed in place, which keeps the two questions apart: whether a digit is in the code and where it goes. A countdown shows when the next locks arrive. The page says they come at 00:00 your time, but each new set is scheduled for 13:00 UTC, so a player in Europe or the Americas gets it in the afternoon or morning of the date it carries. A date picker and archive open earlier days.

The game plays in a browser on a desktop or a phone with no account. It is free with ads around the board; a Puzzleship Premium plan removes them and adds extras, and Puzzleship also sells printable booklets of locks. It suits players who like short, exact deduction puzzles and Mastermind-style reasoning without guessing.