The one rule, if you read nothing else
Keep caption text inside a rectangle of roughly 865 x 980 pixels within the 1080 x 1920 frame, sitting 270 pixels down from the top and 65 in from the left. It is NOT centred, and that is the part everyone gets wrong: the button column on the right is wider than the left margin, and the bottom band is more than twice the top. Clear that rectangle and one export works everywhere, with no re-editing per platform. Everything below is why it is where it is. Checked September 2026 — platforms move their interface without announcing it, so treat these as working rules rather than a specification.
Where each platform covers the frame
Instagram and Facebook Reels are now the tightest, and they are one number: Meta unified the Stories and Reels safe areas in March 2026, reserving the top 270px and the bottom 670px — 35% of the height, because the bottom stacks the caption, likes, comments, share, save, audio and the call to action. TikTok reserves 130px at the top, 484px at the bottom and 140px down the right for its button column. YouTube Shorts is the mildest, but its trap is the description: the bottom overlay grows to about 400px once a viewer taps to expand it, so design for the expanded state rather than the collapsed one. Taking the worst case on each edge separately — no single platform is strictest on all four — is what produces the rectangle above.
The bottom edge is the one that catches people
Almost every caption mistake is a line placed too low. The bottom of the frame feels like the natural home for subtitles because that is where they sit in film and television — but in short-form that band belongs to the platform. Move captions toward the middle third of the frame. It looks unusual for about a day and then looks normal, and it is what most successful short-form does.
Auto-captions make the problem worse, not better
All three platforms now switch their own AI captions on by default, and those appear in the bottom band regardless of what you burned in. If your own captions are also near the bottom you get two sets of words stacked on each other. Burning captions in higher up avoids the collision — and gives you control of the face, size and timing, which platform captions never do.
Check it on a real frame
Numbers are a starting point; a frame is the answer. Export one still from your clip and put it through the free safe zone checker on this site — it draws each platform’s covered area over your own image, in your browser, so you can see whether the line survives rather than measuring pixels by hand.
Questions
What is the safe zone for vertical video?
As a single working rule: an 865 x 980 rectangle inside a 1080 x 1920 frame, 270 pixels down from the top and 65 in from the left. It is not centred — the right-hand button column is wider than the left margin and the bottom band is deeper than the top. That clears TikTok’s button column and caption block, Meta’s unified Reels area on Instagram and Facebook, and YouTube Shorts’ controls, so the same export works everywhere without re-editing.
Can I just use the platform’s own captions?
You can, and for a straightforward talking-head clip they are adequate. They are a poor fit for anything with names, terminology or a second language, because they mishear those consistently and you have no control over the correction. They are also styled by the platform, so your clips look like everyone else’s.
Do safe zones change?
Yes, and without announcement. TikTok added a button at the bottom-right in January 2026 and YouTube expanded its subscribe area in late 2025, each pushing an edge inward. This is why the conservative rectangle above is worth using rather than measuring each edge to the pixel: it has margin for the next change built into it.
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