Where each platform covers your video, why the three safe zones do not overlap, and why one master cannot serve all of them.
Every platform overlays your video with its own interface. The area it covers is the safe zone, and getting it wrong means your captions, subject or call to action are physically unreadable on someone else's screen. The specifications differ per platform and they change.
A safe zone is the region of your frame that will not be covered by platform UI. It differs by platform, by placement of the interface, and by whether you are looking at the app or a browser. There is no single correct safe zone, only per-platform ones.
The practical rule is to keep anything load-bearing inside the safe zone: captions, the subject's face, your logo, any on-screen call to action. Backgrounds can bleed to the edge freely.
TikTok's right-hand action column occupies roughly the right 15% of the frame. The caption and username block sits at the bottom left, and the top of the frame carries the search and activity affordances. On the web player the proportions differ again.
For planning purposes, keep critical content within the central 80% horizontally and avoid the bottom 20% vertically. Treat those as a starting approximation rather than a specification to design against, because the interface moves.
Reels overlays a right-hand action column similar to TikTok, a caption block at the bottom, and a progress indicator that eats into the bottom edge. Shorts stacks its controls on the right and adds a title and channel row at the bottom.
Shorts is the most forgiving of the three for vertical placement and the least forgiving for the right edge. Captions placed low will be covered on Reels in a way they will not be on Shorts.
Do not export once and assume. Render at the final aspect ratio and compose with per-platform safe-zone guides rather than a single master, because the overlays do not overlap across platforms.
This is the argument for rendering per destination rather than per source. A single vertical master pushed to three platforms will be correctly composed for at most one of them.
Platform interfaces are redesigned regularly and safe-zone figures we publish will go stale. Treat any safe-zone number, including ours, as current to the reviewed-on date and verify against the live app before a production campaign.
We would rather tell you to check than present a stale figure as authoritative.
ReelsAudio renders faceless episodes with consistent voice and music, varied structure, and loudness normalised per platform.