Image Steganography
Hide secret text messages inside images using LSB encoding. Optional password protection for extra security.
Upload Image
Choose source image to hide message in
Encoded image will appear here
Tips
- • Use PNG format only (JPG compression destroys hidden data)
- • Larger images = more character capacity
- • Password adds XOR encryption layer
- • Share as file, not screenshot
What is Image Steganography?
Steganography is the ancient art of hiding secret information in plain sight. While cryptography makes messages unreadable, steganography conceals the very existence of the message. The word comes from Greek: steganos (covered) and graphein (writing).
Digital image steganography hides text data within image files. Our tool uses the Least Significant Bit (LSB) technique, which modifies the tiniest component of each pixel's color value. These changes are invisible to the human eye but can be decoded by the right software.
Unlike online converters that upload your data, our tool processes everything locally in your browser. Your secret messages and images never leave your device, ensuring complete privacy.
How LSB Encoding Works
Convert to Binary
Each character becomes 8 bits (e.g., "A" = 01000001)
Modify Pixels
Replace last bit of Blue channel value with message bit
Save as PNG
Lossless format preserves every modified pixel exactly
Key Features
Encode & Decode
Hide messages in images and reveal hidden ones
Password Protection
Optional XOR encryption for extra security
Capacity Indicator
See exactly how much text fits in your image
Activity History
Track recent encode/decode operations
100% Private
Everything happens in your browser
PNG Export
Lossless output preserves hidden data
Common Use Cases
Private Communication
Send messages that look like ordinary photos, ideal for sensitive information.
Digital Watermarking
Embed ownership or copyright information invisibly in your images.
Easter Eggs
Hide fun messages or clues in images for games, puzzles, or surprises.
Document Authentication
Embed verification data in official document images.
Frequently Asked Questions
What is steganography?
Steganography is the practice of hiding secret information within ordinary, non-secret data. Unlike encryption that makes data unreadable, steganography conceals the very existence of the message. The term comes from Greek words meaning 'covered writing'.
How does LSB steganography work?
LSB (Least Significant Bit) steganography modifies the last bit of each color value in an image pixel. Since each pixel has RGB values (0-255), changing the last bit creates a difference of only 1 in color value—imperceptible to the human eye. Your message is converted to binary and stored across many pixels.
Why must I use PNG format?
PNG uses lossless compression, preserving every pixel exactly. JPG and other formats use lossy compression that modifies pixel values to reduce file size, which destroys the hidden data. Always save and share steganography images as PNG files.
How much text can I hide in an image?
Capacity depends on image dimensions. The formula is (Width × Height) ÷ 8 characters. A 1000×1000 pixel image can hold about 125,000 characters. Our tool shows a capacity indicator so you know exactly how much space is available.
Is my data uploaded to a server?
No. All encoding and decoding happens directly in your web browser using JavaScript and HTML5 Canvas. Your images and messages never leave your device. This makes our tool completely private and secure.
What does password protection do?
Password protection adds an XOR encryption layer before hiding the message. Even if someone knows to look for hidden data, they can't read it without the correct password. The message appears as garbled text without decryption.
Can steganography be detected?
Statistical analysis tools called steganalysis can potentially detect LSB changes in images. However, for casual use, the changes are invisible to human eyes and standard image viewers. For high-security needs, combine steganography with strong encryption.
What happens if I compress the image?
Compression (like converting to JPG, posting to social media, or using messaging apps) will destroy the hidden message. The subtle bit changes are lost when pixels are recalculated during compression. Always share as an uncompressed PNG file.
Can I hide files instead of text?
This tool is designed for text messages. Hiding files would require converting them to binary and encoding across many more pixels. While theoretically possible, large files could make the image visibly distorted and detection easier.
Is steganography legal?
Steganography itself is legal in most countries. It's a technique used for privacy, watermarking, and secure communication. However, using it for illegal purposes (hiding illicit content, evading legal obligations) may be prosecuted. Use responsibly.