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How to make a vertical 9:16 video on a Mac
By Himanshu Ranjan · Updated 8 November 2026
To make a vertical video on a Mac, select the clip and choose between two FileDial tools. Frame › Crop to 9:16 (vertical) fills the portrait frame by cutting the sides. Frame › Fit for Stories, Reels & TikTok (9:16) keeps the whole picture. Both save a new copy offline.
What 9:16 means
9:16 is a portrait shape, taller than it is wide, and it is the format that Snapchat, TikTok and the vertical feeds on YouTube and Instagram are built around. A phone held upright shows a 9:16 picture full screen. A widescreen 16:9 clip placed in that frame leaves large empty areas above and below.
Converting means deciding what happens to the picture that does not fit. You can cut the sides off or you can keep everything and accept bars.
Crop to fill the frame
Frame › Crop to 9:16 (vertical) cuts a portrait-shaped area out of your video. It suits clips where the subject sits in the middle, such as a person talking to camera or a product shot. The sides are lost, so check the result for cut-off faces or text.
- Select the widescreen video in Finder.
- Hold the right Option key to open the dial.
- Choose Frame › Crop to 9:16 (vertical).
- Play the new copy and check that the subject stays in frame.
Fit when you cannot lose anything
Frame › Fit for Stories, Reels & TikTok (9:16) keeps the entire picture and fits it into a vertical frame, so the picture appears smaller with space around it. Use it for screen recordings, charts or wide scenes where every edge matters. If your target is a feed post rather than a story, use Frame › Fit for Instagram feed (4:5) or Fit for Instagram square (1:1).
See the resize-video-for-Instagram guide for platform shapes in more detail.
Planning for vertical feeds
Social apps overlay buttons, captions and profile names on vertical video, so keep key content away from the very top and bottom and the right edge. A crop that centers the subject helps, but check how the clip looks inside the app preview before posting widely.
If you film for vertical from the start, hold the phone upright. A video filmed vertically needs no crop at all, and the quality is higher because no pixels are thrown away.
Combining shapes in one workflow
A typical workflow is trim, crop or fit, add captions and compress. Because each tool saves a new copy, run them in that order and use the latest result as the next input. Delete intermediate files at the end to save space.
For landscape and portrait versions of the same clip, make both from the original. That avoids stacking edits and keeps the best quality in each.
Resolution, quality and common mistakes
A 9:16 frame has a different pixel count from a 16:9 one. Cropping a 1920 by 1080 video to 9:16 leaves a tall strip only about a third of the original width, so the vertical picture has fewer pixels than the original suggests. A 4K source gives you much more to work with, so start from the highest quality file you have and avoid cropping an already-compressed copy.
Fit keeps the whole picture but shrinks it to fit the width of a vertical frame, so the content can look small on a phone. For screen recordings, text may become hard to read, so test one clip on a phone before sending a batch.
Common mistakes: cropping on the centre when the subject is off to one side, forgetting the platform's own interface overlays, mixing up crop and fit, and compressing twice, once for the crop and once for upload. Re-encoding costs a little quality each time, so keep the number of passes small.
FileDial is the right tool for fixed, repeatable shapes on a batch of clips. It is not the right tool when you want to follow a moving subject with the frame, where an editor with keyframes does the job.
Platform guidance
Platforms change their rules, so check each platform's own help pages for current duration, size and shape limits before you export. This page does not state platform limits because they change often. The resize-video-for-Instagram guide covers that platform's shapes, and the same approach applies elsewhere: make the shape right first, then compress to fit the upload.
Finishing touches
Vertical clips for social often need captions. Adjust › Add auto-captions… transcribes the speech on your Mac and burns it into a new copy, plus an SRT. A short clip looks better trimmed first with Cut › Trim…, and a logo can be added with Adjust › Add logo or watermark…
If the original was filmed sideways by accident, rotate it rather than cropping: see the rotate guide. Everything is processed on your Mac, so unreleased footage stays private.
Questions
What is the difference between crop and fit for 9:16?
Crop to 9:16 cuts the sides so the picture fills a portrait frame. Fit for Stories, Reels & TikTok keeps the whole picture and fits it into the frame, which leaves space around it. After either one, play the result and look for cut-off faces, text or captions near the edges.
Which should I use for a talking-head video?
Crop to 9:16 usually works, because the person is centered and the cut sides hold little of interest. Check the result to make sure the face is not cut off. Crop is the safer starting point for one person facing the camera, and fit is safer for wide scenes or screen content.
Does FileDial overwrite my original video?
No. Both tools save a new copy beside the original, and the result card shows the size before and after. Undo removes the new copy. Because the original is never touched, you can make a cropped version and a fitted version of the same clip and compare them before deciding which to post.
Can I add captions to the vertical video?
Yes. Adjust › Add auto-captions… transcribes speech on your Mac and burns captions into a new copy, plus an SRT file. Nothing is uploaded. The captions are generated on your Mac, so the audio is not sent anywhere for transcription.