Encode, hide &
reveal the unspoken.
Mega Joker turns plain text into six classic ciphers, tucks whole messages inside a photo, and reveals what others hid — no account, no cloud, all yours.
Eight ways to keep a secret.
Every screen is built for one job and gets out of your way — encode a note, break an unknown shift, or slip a message into an image.
Turn text into a cipher — then unlock it.
Pick a cipher, drop in your words, and Mega Joker rewrites them into monospace secrecy. Hand the reverse tool a coded line and it slides the letters right back.
- Six ciphers, from a simple Caesar slide to a keyed alphabet
- Keep the original alongside the encoded version
- One-tap Copy content to share anywhere
Break an unknown Caesar in seconds.
Caught a scrambled line with no key? Feed it to the Cracker and Mega Joker walks every shift until the plain message surfaces — no guesswork required.
- Automatically tests all 25 possible shifts
- Reads out the most likely plaintext
- Perfect for puzzles, escape rooms and note-passing
Learn the six ciphers, then try them.
Not sure whether to reach for ROT13 or Rail Fence? The library explains each one in a sentence — from “letters slide a fixed number of steps” to a zig-zag across rails — and lets you experiment on the spot.
- Plain-language explanation for every cipher
- Atbash mirror, Vigenère keyword, keyed substitution and more
- Tap through to a live try-it-out playground
A closer look inside.
Swipe through the studio — dark, quiet and made for keeping things between you and one other person.
Ready to whisper in cipher?
Download Mega Joker and carry a whole secret studio in your pocket — six ciphers, image hiding and a cracker, working completely offline.
GET IT ONGoogle Play