Steganography
Hide a secret message inside an image
Runs in your browser. Files never leave your device.
How to use Steganography
- Open the picture that will carry the message.
- Type your message, optionally add a password, and check that it fits.
- Download the PNG. To read it, open it again and choose Reveal.
About this tool
Hide a secret text message inside a picture. The message is stored in the lowest bit of each color value, which changes the image too little to see. You can protect it with a password, so even someone who knows a message is there can’t read it.
Switch to Reveal to read a message hidden with this tool. The result is always saved as a lossless PNG, because compressed formats would destroy the hidden bits.
- Works on your device. Nothing is uploaded.
- Free, with no sign-up and no watermark.
- No limits on file count or size beyond what your device can handle.
Questions and answers
How long can the message be?
Each pixel holds three bits, so a 1,000 × 1,000 photo can hide about 370 KB of text. The capacity meter shows how much room is left.
Why did my message disappear after sharing the image?
Messaging apps and social networks usually compress or resize pictures, which wipes the hidden bits. Send the PNG as a file or document instead.
Can I read messages hidden with other apps?
No. Each steganography tool uses its own layout, so only messages hidden here can be revealed here.
Is Steganography free?
Yes. Every tool on ImgImage is free to use, with no sign-up, no watermark and no limit on how many files you process.
Are my files uploaded anywhere?
No. Your files are processed by your own browser and never leave your device. Nothing you open here is sent to a server.
Does it work on my phone?
Yes. It works in any modern browser on phones, tablets and computers. Large files are processed faster on a computer.