Codebreaker

How to play

1. Choose a color for every slot using its menu, then select Check code or press Enter. Colors can repeat, and the numbered color labels identify the same colors throughout the board.
2. Exact counts colors in the correct slot. Misplaced counts correct colors in different slots. These are totals, not markers for particular slots; each color occurrence counts at most once.
3. Use the previous guesses and the attempts-left counter to refine your next code. Getting every slot exact completes the puzzle; using all attempts ends it and reveals the code.

Head-to-head rules

Find the four-slot color code within eight guesses before your opponent. Both players get the same puzzle and start together, with 3 minutes to finish. Completion time decides the match; fewer moves or a higher solo score do not beat an earlier correct finish. Finishes within 0.1 seconds draw. If neither player finishes before time runs out, the match is a draw.

Your moves and answers stay private. Leaving through the game controls forfeits the match; closing the page does not pause its clock.

Real-player matches update this game's own Elo rating. Daily and practice results keep their separate progress and never change Elo.