Codicino: Secret Codes

Kids invent a real cipher, encode a note, and print a paper wheel to keep playing away from the screen. Two historic codes, explained simply. No ads & data, fully offline

Codicino — The Secret Code Game

With Codicino, kids invent a secret code, encode a note, and swap it like real secret agents. The best part: the game keeps going away from the screen, on paper.

How it works

Your child picks a code, types a sentence, and watches it turn letter by letter into a mysterious message. Copy it onto a slip of paper — only someone with the same key can read it.

Two real ciphers

• The Caesar cipher, the same one Julius Caesar used 2,000 years ago: turn the wheel and the alphabet shifts
• The keyword cipher: pick a word and the alphabet gets scrambled

These are the first real concepts of cryptography, explained in plain words. A dedicated section tells kids what a code is, what a key is, and why — surprise — codes can be cracked. It's a fun game, not a safe.

Off the screen, onto paper

A grown-up prints a PDF with the cipher wheel to cut out and assemble with a split pin, plus the conversion table and instructions. From there, no device is needed: kids swap paper notes at school and decode them with the wheel in hand.

To share a code between friends there's a QR that holds the key — never the messages — created and scanned from the Parents Area.

A kind game

Codicino asks kids for a small promise: codes are for playing and keeping secrets between friends, never for mocking or leaving anyone out.

Made for families

No data collection. No accounts, no ads, no tracking. Everything runs on the device, even without internet. A protected Parents Area for grown-ups.

Build your code, print the wheel, and swap secret notes.