How to Blur Sensitive Info in a Screenshot on Mac
Before you share a screenshot, hide the private bits. Here's how to blur or black out sensitive information on a Mac — safely.
Can you blur part of a screenshot on a Mac?
Not really with the built-in tools. Preview's markup can draw a filled shape over something, but that's easy to move or delete and it doesn't truly blur. For a proper blur or redaction you need a screenshot editor like Shotstrix.
Why a black box isn't enough
A drawn shape or solid rectangle can be moved, deleted, or — if the file keeps layers — removed entirely, and blur that's too light can sometimes be reversed. The safe approach is to flatten a real blur or solid redaction into the image before you share it.
Blur anything with Shotstrix
Shotstrix (free) has a blur tool right in the editor: brush over card numbers, emails, names, or faces and they're blurred into the image. Copy or save and the sensitive area is gone for good — nothing to peel back.
How to blur a screenshot in Shotstrix
- 1 Capture the screenshot
Grab the region or window you need to share.
- 2 Pick the Blur tool
Select Blur in the Shotstrix editor.
- 3 Brush over private info
Paint over anything sensitive — numbers, emails, faces.
- 4 Copy or save
The blur is baked into the final image.
Get Shotstrix — free
Shotstrix is a free screenshot and screen-recording tool for macOS — scrolling capture, OCR, annotation, blur, GIF recording, and share-ready backdrops, with no account and no watermark.
Free · Universal (Apple Silicon + Intel) · macOS 14 Sonoma or later
Frequently asked questions
Can Preview blur a screenshot? +
Not really — Preview can draw a shape over something, but it doesn't truly blur and it can be undone. Shotstrix has a real blur tool that flattens into the image.
Is blurring safe for sharing sensitive info? +
With Shotstrix the blur is flattened into the saved image, so the original pixels are gone. Always double-check the final image before sharing it.
Is the blur tool free? +
Yes — blur is part of Shotstrix's free editor.