How to Use Unch to Conceal Your Messages with Invisible Characters

Are you looking for a clever and discreet way to hide messages within your writing? You’re in luck! Unch allows you to conceal text within another text by using invisible Unicode characters. It’s like a digital version of invisible ink!

In practice, Unch uses Unicode Variation Selector characters, ranging from \nE0100 to \nE01EF, to mask your secret message. Your plain text serves as a cover, and voilà! Only those who know the trick can reveal the hidden content.

How does it work?

1. Your message is first encoded in Base64.
2. Then, for each character in the result, a variation selector is added.
3. This esoteric text is then inserted into your innocent-looking message.
   And just like that, you have a seemingly ordinary text that holds a well-kept secret! Your recipients won’t suspect a thing.

Using Unch is simple. You can:

• Download a precompiled binary from the GitHub releases page.
• Compile the source code yourself in Go (version 1.22.0 or higher required).
• Use the official Docker image.

Then, just run the unch command with your message and the cover text. For example:

unch "My secret message" "Hey, what's up?"

You can also use options to decode a hidden message with -d or --decode, generate random fake text with -l or --lorem, and even remove the final line break with -n.

Here are a few usage examples:

unch "Meet at 10 PM" "Shall we watch a movie tonight?"
unch -l "I am a secret agent"
unch -d "Shall we watch a movie tonight?"

With Unch, you can share information with your friends or colleagues for fun (but don’t get too serious—remember, it’s not encrypted).

Discover more here.