How to hide a message in an image — and test the shared copy
Choose Image, enter a message and a decoding key, then download the picture. Always decode the copy downloaded from the platform: a successful original does not prove that the published copy survived.
Create and check your image
Open the workspace, choose Image and an artwork or a picture you have permission to use. Enter up to 800 UTF-8 bytes: Cyrillic letters and emoji may use more than one byte. Keep the suggested random key or enter your own.
Create the result and click Download picture. The site saves a JPEG automatically and checks recovery before offering it. Keep the downloaded picture and the portable encrypted token as fallbacks.
What we checked with Facebook
On 17 October 2026, two user-supplied Facebook JPEGs at 810 × 540 were compared with their respective 1536 × 1024 originals. The updated decoder recovered the exact encrypted token from both. The second case was also confirmed by the user with their decoding key.
This is evidence for those two files, not a controlled success-rate study or a Facebook compatibility guarantee. Other compression, resizing, crops, screenshots and filters may destroy data. A legacy PNG-only image does not gain this resilience automatically.
Share and recover
Post the complete picture, download the published copy, and try that file in Read before relying on it. Send the decoding key separately through a trusted channel. The recipient selects the downloaded image and enters the key.
If recovery fails, ask for the original file or the encrypted token from the sender's result. The key cannot recreate erased payload data. Do not upload a sensitive image to an unrelated repair service: the image can carry private encrypted data.