Hide a Message in a Photo
Slip a secret note inside an everyday photo so it looks completely ordinary — then share it knowing only the right person can read it.
Drop an image to hide a message in
Drag & drop, paste, or pick a file
PNG · JPG · WebP — processed on your device
A note hidden in plain sight
Hiding a message in a photo is one of the oldest tricks in secret communication, brought up to date. You drop in a normal picture — a sunset, a pet, a screenshot — type your note, and the tool tucks the words invisibly into the image. Sent to a friend, it looks like you just shared a photo.
The change is far too small to notice: only the lowest bit of each colour is touched. With a password, the note is encrypted as well as hidden, so it stays a secret even if someone goes looking for it.
How to hide a message in a photo
- Choose a photo. Drag, choose, or paste the picture you want to use as the cover.
- Write your note. Type the message and, if you want, a password to encrypt it. The capacity meter shows how much fits.
- Hide and share. Click Hide message, download the PNG, and share that file with the person who should read it.
Share the file, not a screenshot
Send the downloaded PNG as a file attachment, not a screenshot or an in-chat preview. Screenshots and auto-compression re-encode the image and wipe out the hidden message, so the recipient would find nothing.
Hiding a message in a photo: a practical reference
What actually happens to the photo, how long a note can be, and how to make sure your recipient can still read it.
- Method
- LSB (least-significant-bit) encoding — the lowest bit of each pixel's red, green and blue value is replaced with one bit of your message. The alpha (transparency) channel is left untouched.
- Visible change
- At most ±1 on a 0–255 colour scale per channel — far below what the eye can perceive, so the picture looks identical.
- Password option
- Optional. With a password the message is encrypted before embedding using a key stretched from your password with AES-256-GCM + PBKDF2 (SHA-256, 600,000 iterations) plus a random salt; without one, the bits are hidden but not encrypted.
- Output format
- Always a lossless PNG. JPG and WebP re-compress the pixels, which would wipe out the hidden bits, so the tool never exports those.
- File size impact
- Negligible content change — only one bit per colour is touched — though the saved PNG may differ in size from the original simply because it's re-encoded as lossless PNG.
How much fits
A typical phone photo has plenty of room. A 4032 × 3024 shot (a common 12-megapixel size) holds about 4,465 KB of text, and even a 1024 × 768 image holds about 288 KB — far more than a short note needs. The capacity meter shows the limit before you commit.
Security: it hides, it doesn't lock
Sharing it safely is about more than hiding. Steganography hides that a message exists; it does not, on its own, scramble what the message says. Anyone who knows to run this kind of image through an LSB extractor can read an un-passworded message. For real secrecy, set a password so the text is encrypted as well as hidden — and remember that LSB is not designed to survive forensic statistical analysis. If the photo will pass through other people or platforms before it reaches your recipient, a password matters: it keeps the note unreadable even if someone suspects the image is carrying one.
Tips that actually matter
- Send the downloaded PNG as a file/document attachment, not as an in-chat photo — most messaging apps re-compress inline photos and that destroys the hidden message.
- Pick a normal-looking everyday photo as the cover; an image that already looks like something you'd casually share draws no attention to itself.
- Agree the password with your recipient through a different channel, never inside the same photo or message.
More steganography tools
Frequently asked questions
Will my friend see that the photo has a message?
No. The photo looks completely normal. Only by running it through the Extract tab (with the password, if any) can the message be revealed.
Do both people need an account?
No accounts at all. You hide the message and send the PNG; the recipient opens this tool's Extract tab to read it.
Can I hide a long message?
Yes, within the image's capacity — about one character per three pixels. The meter shows the limit; pick a larger photo for a longer note.
Where is my image processed?
The hiding and extracting happen in your browser, so the new file is created on your own device. How any data associated with the tool is handled is described in our privacy policy.
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