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How to crop a video on a Mac
By Himanshu Ranjan · Updated 8 November 2026
FileDial crops video with fixed shapes: Frame › Crop to square, Crop to 9:16 (vertical), Crop to 16:9 (wide) and Crop black bars. Select the file in Finder, hold the right Option key and run the one you need. It saves a new copy offline and keeps your original.
Choose the crop that matches your goal
Cropping removes the edges of the picture so the remaining area fits a new shape. FileDial offers specific crops rather than a drag-and-drop box. That makes common jobs quick, but it also means you cannot pick any arbitrary rectangle.
- Frame › Crop to square: a 1:1 picture, useful for profile clips and square posts.
- Frame › Crop to 9:16 (vertical): a portrait picture for Stories, Reels and TikTok.
- Frame › Crop to 16:9 (wide): a widescreen picture, for example from a vertical clip.
- Frame › Crop black bars: removes the black bands around the picture.
Steps in FileDial
The process is the same for each crop.
- Select the video in Finder.
- Hold the right Option key to open the dial.
- Open Frame and choose the crop that fits.
- Open the new copy, saved beside the original, and check that nothing important is cut off.
Crop, fit or resize
Cropping throws away part of the image. Fitting keeps the whole picture and adds bars or padding to match a shape. FileDial has fit tools as well, such as Frame › Fit for Stories, Reels & TikTok (9:16), Fit for YouTube (16:9) and Fit for Instagram square (1:1). Choose crop when you would rather lose the edges than see bars.
Black bars in a video are part of the picture. Frame › Crop black bars removes them so the content fills the frame, which is handy for screen recordings from a phone or letterboxed movies you shot yourself.
Planning the crop before you shoot
The best crop is the one you do not need. If you know the video is headed to a vertical feed, frame the subject in the middle of the shot while filming, so a 9:16 crop keeps everything important. For a square post, leave space around the subject for the same reason.
If you are working with footage you cannot reshoot, preview the crop in your head: a 16:9 picture cropped to 9:16 keeps only about a third of the width, so wide group shots and side-by-side screen content will lose a lot.
Cropping screen recordings and phone captures
Screen recordings from a phone often come with black bands from the status area or the aspect ratio, and Frame › Crop black bars removes them in one step. For a desktop recording that includes a menu bar or dock you do not want, a fixed crop will not isolate a window, and a free-form tool in an editor is the better choice.
After cropping, the picture is a new size. Check it plays properly and use a Compress tool if the file is large.
Quality, size and common mistakes
Cropping changes the number of pixels in the picture, and what you do next decides the quality. Cropping a 4K video to a square leaves a smaller picture that is still sharp, while cropping a 720p clip to the same shape leaves very little. Check the size of the cropped area before you commit.
A common mistake is cropping first and checking later. Play the new copy and look at the edges, because cut-off heads and clipped text are easy to miss. Another is cropping when you should fit: if the whole picture matters, such as a slide or a chart, choose a Fit tool, which keeps everything, instead of a crop, which does not.
File size can go down because there are fewer pixels, but the video is re-encoded, so it is not guaranteed. Read the result card, then use a Compress tool if you need a smaller file. FileDial is the right tool for the common shapes: square, vertical, wide and black bars. It is not the right tool for lifting one window out of a desktop recording or drawing a custom rectangle, where an editor is better.
Checklist before cropping
Decide on the destination first, then crop once.
- Name the target shape, such as square or vertical.
- Check where faces and text sit in the frame.
- Run the tool and watch the edges of the new copy.
- If anything important is cut, use a Fit tool instead.
- Compress last, not first.
Free options on a Mac
QuickTime Player can trim, rotate and combine clips but has no crop command on its menu. iMovie has a cropping control in its toolbar for changing how a clip fills the frame, which suits a single project but needs a project to be set up. For a quick one-off with a fixed shape, a dedicated tool is faster. For a free-form crop you will need an editor such as iMovie.
Everything in FileDial runs on your Mac and nothing is uploaded, which matters for clips of people or screens.
Questions
Can FileDial crop to any rectangle?
No. It offers fixed crops: square, 9:16 vertical, 16:9 wide and black bars. For a freehand crop use an editor such as iMovie, then use FileDial for compressing or converting afterwards. Fixed crops are quick, while a free-form crop needs an editor such as iMovie, which you can then follow with FileDial's tools.
How do I remove black bars from a video?
Select the video and run Frame › Crop black bars. It saves a new copy without the bands around the picture. The original is left unchanged beside it. Letterboxed footage and phone screen recordings are the typical cases where this tool helps.
What is the difference between crop and fit?
Crop removes part of the picture so it fills a shape. Fit keeps the whole picture and adds space around it. FileDial offers both under Frame, such as Crop to 9:16 and Fit for Stories, Reels & TikTok (9:16). Fit keeps everything and adds bars, which suits screen recordings where every edge carries information.
Does cropping make the file smaller?
Not reliably. Cropping changes the picture area, but size depends on re-encoding settings. Check the result card, which shows the size before and after, and use a Compress tool if you need a smaller file. A new picture size sometimes lowers the file size and sometimes does not, so read the result card.