SnapMark / Guides / Blur sensitive information

How to blur sensitive information in a screenshot

A screenshot can reveal more than the main subject. Before sharing it, inspect the full image and hide private details with enough coverage to prevent accidental disclosure.

SnapMark workflow: capture the page, use the blur tool in the local annotation editor, verify every sensitive area, then inspect the exported file separately before sending it.

Information worth checking

  • Names, email addresses, phone numbers, and profile photos.
  • Account IDs, order numbers, customer records, and internal URLs.
  • Payment details, balances, invoices, and transaction references.
  • Private messages, support conversations, and browser notifications.
  • API keys, access tokens, passwords, recovery codes, and QR codes.
  • Tabs, sidebars, background windows, and unrelated page content.

Step-by-step workflow

  1. Capture only what is needed. Use Visible mode when a full-page image would expose unnecessary content.
  2. Review the entire screenshot. Inspect the corners, header, footer, sidebars, and any floating panels.
  3. Apply blur with a margin. Cover the sensitive text or image completely rather than tracing the exact character boundary.
  4. Zoom in and verify. Confirm that the original value is no longer readable in the edited image.
  5. Export the final file. Save it as PNG, JPG, or PDF.
  6. Open the exported file separately. Verify that the correct edited version was exported and no unedited copy is being shared by mistake.

Blur versus solid redaction

Blur is useful for ordinary screenshots and visual explanations, but highly sensitive material may require a solid opaque redaction performed by a tool specifically designed for secure document redaction. Do not assume a light blur is suitable for secrets, legal records, or regulated data.

Never publish active credentials. When a screenshot has exposed an API key, password, or token, revoke and rotate the credential even after editing the image.

Local processing

The current SnapMark extension performs screenshot annotation and export locally in the browser and does not automatically upload captured images to SnapMark servers.

Related guides

Capture a full webpage in Edge →
Capture internal scroll areas →