Kode

Kode is a daily code-breaking puzzle in the spirit of Mastermind, turned into pure deduction. Instead of guessing and getting feedback, you start with the guesses and the feedback already on the board. Every clue row is a four-digit attempt marked with two counts: a triangle for a right digit in the right spot, and a dot for a right digit in the wrong spot.

The counts never say which digits they mean, so the work is comparing rows: a digit that appears in a row scored zero can be crossed out everywhere, and two rows that differ by one digit tell you about that digit. Each puzzle has one solution.

When you have it, type the code on the keypad. You have three tries, and your score depends on how many tries and how much time you take. Tapping a clue tile cycles a pencil mark through red, yellow and green as a notepad that never affects the grading.

A new numbered Kode arrives at midnight UTC for everyone, an archive holds past puzzles, and streaks and stats are kept on your device. It is free, needs no account, shows no ads, and can be played in English, Spanish, French, German, Portuguese and Japanese.

Every board is checked by a solver before it goes live: a board that cannot be cracked by deduction alone, without trial and error, is thrown out. Each past Kode in the archive comes with spoiler-free hints, such as the sum of the digits, and a step-by-step solution, so a missed day can still be worked through.