Let's jump right in, no beating around the bush. Here's the best way to format and export your videos for TikTok (and any 9:16 platform) in Final Cut Pro.
Set your project to 9:16
TikTok wants a 9:16 portrait ratio, 1080 by 1920, and your video should fill the entire canvas (turning your phone sideways isn't something most people want to do). You can either start a new project at those dimensions or change them after editing. If you've already cut your video, go up to the project, click Modify, and set it to 1080 by 1920.
Fill the frame
If you shot vertically, on your phone or by turning your camera sideways, you won't have to adjust much. But if you shot in landscape, you'll need to scale your image up until it fills the whole frame. That does crop out part of the shot, so reframe as needed, just remember to hit the keyframe button when you start adjusting so all your changes are saved.
Export the right way
When you export, use the Apple Devices 1080p preset and set your video codec to H.264. One thing to double-check: TikTok caps uploads around 287 MB, so make sure your export isn't over that before you post.
Edit faster with my custom shortcuts
Grab my free Final Cut Pro keyboard shortcuts cheat sheet. It's the exact custom setup I use to edit every video, and it'll shave time off every session.
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