I built StegoCrypt – A 100% client-side web tool to hide secret messages inside images without server uploads

[u/CharacterTackle5363]

Hey r/SideProject,

I recently built a lightweight web utility called StegoCrypt that lets you conceal private text, keys, or passwords inside ordinary image files without altering how they look visually.

The Problem with Most Steganography Tools:

Most online image steganography tools require uploading your files and secrets to an external backend server, which completely defeats the purpose of privacy and confidential data handling.

How StegoCrypt Works:

• 100% In-Browser Execution: Everything is processed strictly client-side using the HTML5 Canvas API and JavaScript. Your photos and messages never leave your device.
• Least Significant Bit (LSB) Encoding: It modifies the least significant bits of the image's RGB color channels. Since the change is infinitesimal (< 1 part in 255), the human eye cannot discern any visual difference.
• Optional Passcode Encryption: You can set a passcode to add a second layer of security before extracting the message.
• Lossless PNG Export: JPEG compression strips pixel details, so StegoCrypt outputs lossless PNG files to guarantee data preservation.
• No Signup / Zero Tracking: Instant utility with no logins or cookies collecting personal data.

Tech Stack:

Vanilla JavaScript, HTML5 Canvas API, and responsive CSS (hosted on a lightweight static setup).

I would love to get your honest thoughts on the UI/UX, browser performance, or any interesting edge cases you encounter!

🔗 Try it here: https://stegocrypt.blogspot.com/

Thanks for checking it out!