MotionShineShort answer: for faces, use the free blur faces in a video tool. It runs in your browser, finds faces itself, and lets you drag a box over anything else, such as a number plate or a screen. For any other area, Apple's Final Cut Pro guide describes adding a shape mask to an effect such as Gaussian blur, so the blur lands inside or outside the shape. iMovie's Apple page, checked on 23 October 2026, does not mention a blur tool. MotionShine does not blur video.
Facts about Apple's apps come from Apple Support pages read on 23 October 2026. Facts about the free tool come from its own page on this site. This is a description of what the pages say, not a hands-on test of Final Cut Pro.
Which method fits
| Need | Best fit | Source |
|---|---|---|
| Hide faces of people in a clip | Blur faces in a video tool | The tool's page |
| Hide a plate, a screen or one area for the whole video | Same tool, drag a box over it | The tool's page |
| Blur any shape, or an area that moves | Final Cut Pro shape mask with an effect | Apple Support |
| Blur in iMovie | Not found on Apple's iMovie welcome page | Apple Support |
| Blur in MotionShine | Not available | This site |
Method 1: blur faces free in your browser
The blur faces in a video tool says it checks every frame for faces with a small face detection model, draws a box on each, and follows it as the person moves. Then it pixelates, blurs or covers each face in black and saves an MP4 with the sound kept. Nothing is uploaded, because the face finder runs in your browser tab.
How to use it:
- Drop in the video.
- Wait while the faces are found. The tool shows how many.
- Press Play and watch it with the faces hidden.
- Click a face you want to keep, such as your own.
- Drag across the picture to hide something else, such as a screen or a plate.
- Pick Pixelate, Blur or Black, then save.
- Watch the finished file before you post it.
Honest limits, from the tool's own page:
- It is built for faces. A hand drawn area is always a box, and it covers that area for the whole video. It does not follow a moving object.
- A face finder can miss a face for a moment. The tool keeps each box on for 10 frames after a face is lost to cover quick turns, but you still need to check the result.
- Black removes the face fully. Pixelation and blur keep some shape and colour, so someone who knows the person well might still recognise them. The tool's page says so itself.
- If your browser cannot draw a true blur, the Blur option pixelates instead.
For an image, not a video, see how to blur text in a screenshot.
Method 2: blur any area in Final Cut Pro
Apple's Final Cut Pro guide says you can add an effect to a clip, open the Video inspector and click the Add Shape Mask button next to the effect name. By default the mask is a partially feathered circle in the centre of the frame. You drag it into place, resize it, and set the softness of the edge. The guide says you can apply an effect such as Gaussian to everything outside or inside the mask shape you define.
It also mentions you can animate the shapes so they follow a moving object or an area while the camera pans, and links to a separate page about animating effect shape masks. Its Draw Mask lets you click points in the viewer for a custom outline. The pages read for this post did not give a step by step for tracking, so check Apple's "Track an effect to a moving object" page for that.
Final Cut Pro is a paid app. Apple's pages read for this post do not state its price, so check the Mac App Store.
What about iMovie?
Apple's iMovie guide welcome page, checked on 23 October 2026, says you can add filters to clips and photos, but does not name the filters. It does not mention a blur or pixelate effect or a way to blur part of a frame. That is "not found", not "it cannot". Look through the filters in your own copy of iMovie.
What about MotionShine?
MotionShine, by the maker of this site, is a free Mac screen recorder with auto zoom, a smooth cursor and a full editor. It does not blur parts of a video, so it is not the tool for this job. If you record a demo and need something hidden, the cleanest way is not to show it at all: close the tab, hide the notification, or blur the finished file with the free tool above. Video editing tips for screen recordings covers planning around private content, and how to edit a screen recording on Mac covers the rest of the cut.
Check before you post
Blur is not proof. Scrub the whole exported file, not just the preview, and watch for a frame where a face or a name slips back. If something is truly private, black is safer than blur.
FAQ
How do I blur part of a video on a Mac for free?
Use the free blur faces in a video tool in your browser. It finds faces, and you can drag a box to hide another area.
Can iMovie blur part of a video?
Not found. Apple's iMovie welcome page mentions filters but does not name them or mention blur. Check the filters in your own copy.
How do I blur an area that is not a face?
In the free tool, drag a box over it, which covers that area for the whole video. In Final Cut Pro, add a shape mask to an effect such as Gaussian, per Apple's guide.
Can the blur follow a moving object?
The free tool's hand drawn areas stay fixed. Apple's Final Cut Pro guide says masks can be animated to follow a moving object.
Does MotionShine blur video?
No.
Is pixelate or blur safer?
Black is the safest. The tool's own page says pixelation and blur keep some shape and colour.
