The size of a TikTok video, and the parts of the screen to keep clear.
Why vertical
TikTok is watched full screen on a phone held upright. A 9:16 video fills that screen; a square or landscape video leaves empty space around it.
What covers a TikTok
The username, caption and sound sit along the bottom of the screen, the buttons run up the right side, and the feed tabs sit at the top. Keep anything important away from those areas, with the biggest margin at the bottom.
Making TikTok videos in Cutlin
Ask for a video and choose the 9:16 shape, labelled Reels, TikTok and Shorts; then Generate for social media, in the video's menu, makes it again at exactly 1080 × 1920, made to the platforms' rules. Make one from a prompt or from your photos, then download it and post it yourself - Cutlin does not post to TikTok for you.