The Piick blind watermark tool lets you hide a secret note or an entire image inside any photo in about 30 seconds — entirely in your browser, no upload, no account. This guide walks through all three modes.

Not sure what’s happening under the hood? Read the principles explainer first.

What the tool does

Three modes, three jobs:

  • Hide text — embed a typed message (up to 1000 characters) inside a cover photo.
  • Hide image — embed an entire watermark image inside a cover photo.
  • Extract — pull the hidden text or image back out of a watermarked photo.

The carrier image must be PNG output end to end. JPEG re-encoding destroys the watermark (see the explainer for why).

Hide text in 4 steps

  1. Open the blind watermark tool. The default tab is Hide text.
  2. Drop a cover image into the first dropzone (or click to browse). The card will show the thumbnail, filename, file size, and Capacity in green — that’s how many bytes of secret data the cover can hold.
  3. Type your message into the Text to hide box. The counter at the bottom right shows N / 1000.
  4. (Optional) Type a password into the Password field. Leave it empty if you don’t need one.
  5. Click Embed. The watermarked PNG downloads, and a preview shows side-by-side with the original.

A 2000×2000 photo holds around 1.5 MB — roughly enough for this entire blog post. A 500×500 photo holds about 91 KB — enough for a short note.

Hide an image in 4 steps

  1. Switch to the Hide image tab.
  2. Drop your cover image into the first dropzone (a regular photo, large is better).
  3. Drop your watermark image into the second dropzone. PNG is required here too — alpha channel is preserved.
  4. (Optional) Set a password.
  5. Click Embed. The result PNG carries the watermark image inside it.

Capacity matters. If the watermark image is bigger than the cover can hold, you’ll see the localized error “Payload too large for this image. Capacity: 91.5 KB. Try a larger cover or a smaller watermark.” The number tells you exactly how much room you had. To fit a 1 MB watermark, you need a cover of roughly 1650×1650 or larger.

Extract in 3 steps

  1. Switch to the Extract tab.
  2. Drop the watermarked image into the dropzone.
  3. Pick Text or Image as the payload type (whichever the embedder used).
  4. If a password was used at embed time, type it here.
  5. Click Extract. The original message appears in the result box, or the original image appears in the preview.

If the tool says “Could not find a watermark”, the most common causes are:

  • The image was saved as JPEG at some point (lossy re-encoding destroyed the bits).
  • The password is wrong.
  • The image never had a watermark.

Output and download

The result is always a PNG. The preview shows the cover (left) and the watermarked version (right) side by side — they should look identical. Click Download PNG to save the watermarked file.

The cover image itself is never modified on disk. You start with the original and produce a new watermarked file; you can keep using the original for other purposes.

What’s safe to use this for

  • Watermarking your own photos with a copyright notice, distributed as PNG.
  • Stashing a private note inside an image you share.
  • Embedding a small logo into marketing images.

What’s not safe:

  • Hiding secrets from anyone motivated to look (this is obfuscation, not encryption — read the principles explainer for details).
  • Sending through platforms that re-encode images to JPEG (Discord, Twitter, WhatsApp all do this — your watermark will be lost).

Open the Piick blind watermark tool and try it now.