How to Hide Text in an Image (Free, In-Browser)
Updated 2026-06-21
To hide text in an image, open a steganography tool, drop in a PNG cover image, type your secret message, and download the result — the text is woven into the image's pixels so it looks identical to the original. The fastest way to do this privately is Steganography — Hide Text in Images, which runs entirely in your browser so the image is never uploaded.
How LSB steganography works
This tool uses LSB (least significant bit) steganography. Every pixel stores red, green, and blue values. Changing the very last bit of each channel shifts a color by at most one step out of 256 — invisible to the eye. The tool packs your message, bit by bit, into those last bits across the image. A 32-bit length header is written first so the reader knows exactly how many bytes to pull back out.
Because the change is so small, the stego image looks identical to the cover image, yet it carries your text inside it.
Step by step: hide a message
- Choose Hide a message mode.
- Drop in a cover image. Use PNG — it is lossless, so the hidden bits survive. BMP and WebP (lossless) also work.
- Type your secret text in the message box. The tool shows a live bytes used / capacity count.
- Click Hide message, then Download PNG.
The downloaded file is your stego image. Share it like any normal picture — the message rides invisibly inside.
To read it back, switch to Reveal a message mode and drop the stego image in. The hidden text appears instantly, ready to copy.
Capacity and the PNG rule
Capacity is generous. Each pixel holds three bits, so the usable space is roughly (width × height × 3 − 32) ÷ 8 bytes. A modest 1000 × 1000 image stores around 375,000 bytes — plenty for paragraphs, not just a sentence. If your text exceeds capacity, the tool warns you to shorten it or use a larger image.
The one rule that trips people up: never use JPEG for the output, and never re-save the stego image as JPEG. JPEG re-compresses pixels and erases the least significant bits, destroying the message. Keep the file as PNG end to end. Likewise, screenshots, social platforms that re-encode images, or editing apps that re-export can strip the data — send the original PNG file directly.
Hiding versus encrypting
Steganography is concealment, not encryption. Anyone who suspects a message is present and runs the same LSB extraction can read it. If the content is sensitive, encrypt the text first with a separate encryptor tool, then hide the resulting ciphertext here. That way even a successful extraction yields unreadable output without the key.
Everything happens locally on a browser canvas — your image and message never leave your device, so there is no server that could log or store either one.
Ready to try it? Open Steganography — Hide Text in Images and tuck a secret message inside your next picture.