hide text in image
Hiding text in an image is different from zipping a file or encrypting a message: the image itself carries the message, nearly indistinguishable from the original to the naked eye, and only someone who knows to look (or has this very tool) can recover it. This page opens the tool already in Hide mode.
At 2 bits per channel, the change is imperceptible or subtle even comparing both images side by side.
AES-256-GCM encryption happens before hiding the text, so even someone who discovers hidden data exists cannot read it without the password.
LSB (least significant bit) is the technique of replacing the least important bits of each color byte with bits of your content, a change small enough that the eye usually cannot tell. This tool uses 1 to 4 of those bits in each red, green and blue channel of every pixel (the alpha channel is never touched), preceded by a 14-byte header with the magic number "STG1", a version, the content size and a CRC-32 checksum to validate extraction.
In most cases, no. At 1 or 2 bits per channel (the recommended default), the difference usually stays above 50 dB PSNR, considered imperceptible to the naked eye. The tool shows a side-by-side comparison and an amplified difference map so you can check before downloading.
Not as a regular photo: WhatsApp, Instagram and most apps recompress images sent as photos, which destroys the hidden text. Send the PNG file as a document/file attachment instead, avoiding automatic recompression.
Everything happens in your browser: the image, the hidden content and the password never leave your device or pass through a server.