Daily · logic
Codebreaker
Crack the vault’s secret colour code. Green = right colour, right spot. Yellow = right colour, wrong spot.
Duel the computer
You each hide a code. Take turns guessing. Crack the computer’s vault before it cracks yours.
Hide your code
Today’s code
How to play Codebreaker
The vault is locked with a secret code of four coloured pegs. Build a guess from the colour buttons and tap Try it. The vault answers with clues:
- Green: one of your pegs is the right colour in the right spot.
- Yellow: one of your pegs is the right colour, but in the wrong spot.
- No light: that peg’s colour isn’t in the code (or you’ve used it more times than the code does).
The clues don’t say which peg earned them. That’s the puzzle. Colours can repeat in the Daily code and in Duels, and every colour also has its own shape, so you never have to tell two colours apart.
Three ways to play
- Daily code: one code for everyone, every day. Crack it in 8 guesses or fewer, then send your result to a friend and see who needed fewer.
- Duel the computer: you hide a code, the computer hides one, and you take turns guessing. Watch the computer’s list of possible codes shrink as it thinks. Rookie only pays attention to green clues; Genius cracks any code in five guesses or fewer.
- Practice: random codes on Easy (no repeats), Classic, or Hard (five pegs, eight colours).
Tips
- Start with two pairs, like red-red-blue-blue. It tells you a lot about four colours at once.
- If a guess lights nothing, every colour in it is out. The game crosses those colours off for you.
- Try to make each guess one that could actually be the answer, given every clue so far.
Why it’s good for you
Codebreaker is pure deduction: holding several clues in mind at once, ruling possibilities in and out, and testing a hypothesis with each guess. It’s a cousin of the old pencil-and-paper game Bulls and Cows, and a favourite of maths teachers because it makes logical reasoning feel like a heist.
Free, no account, works on any phone or computer.