BlueMask

BlueMask is a local image-redaction tool. Secure masking replaces covered pixels before you share a photo or screenshot.

Mask an image

Local processing · No uploads

Drop an image here

PNG, JPEG or WebP · Paste with ⌘V / Ctrl+V

Choose an image, then draw over what you want to hide.

Blur can leave recoverable details.

Bluethroat recommends secure masking for sensitive data.

Secure masking Bluethroat recommended

Replaces covered pixels with a solid patch. Use for names, faces and private messages.

Cosmetic blur Appearance only

Softens pixels without securely removing them. Use for backgrounds and visual effects.

This changes the method for new regions. Existing masks keep their method.

Some regions are only blurred.

Bluethroat recommends secure masking for sensitive data.

Why Paranoia Mode exists

How do you know Bluethroat Labs isn’t uploading your photo or extracting sensitive details from it?

You can check that BlueMask works with your device disconnected. While there is no network connection, this page cannot upload your photo or send its contents to our servers.

  1. Download the offline edition.Everything is included in one HTML file.
  2. Disconnect before opening your image.Turn off Wi-Fi and mobile data; unplug Ethernet.
  3. Open the file, mask and save.Review the download. Close BlueMask before reconnecting.

Your device controls that connection; this button cannot disconnect it.

Offline editing shows that no server is needed. It does not certify the code or your device.

Download offline edition