Codes for spies, puzzles and treasure hunts
Type a message and turn it into a secret code instantly – or paste a code and decode it. Choose Morse code (and listen to it beep), the Caesar cipher that shifts every letter, Atbash which swaps A↔Z, B↔Y…, the number code A = 1, B = 2…, or mirror writing.
Perfect for scavenger hunt clues, classroom lessons about codes, escape-room style birthday parties or just passing secret notes. Everything happens in your browser – nothing is sent anywhere.
How to use
- Choose a code.
- Choose encode or decode.
- Type or paste your message – the result appears instantly.
- Copy it, swap it back, or play Morse code as sound.
Ideas for using it
- Morse. SOS → ... --- ...
- Caesar (shift 3). HELLO → KHOOR
- Number code. CAT → 3-1-20
- Atbash. SECRET → HVXIVG