Where to Put Subtitles on Reels, TikTok and Shorts
Where to put subtitles on Reels, TikTok and Shorts: the safe zone each platform publishes, caption size for vertical video, and a check to run before you post.
Put subtitles on Reels, TikTok and Shorts in the lower middle of the frame: above the bottom third, where the platform's caption, username and buttons sit, and below the strip at the top. Meta's guidance for Instagram Reels is to keep roughly the top 14 percent and the bottom 35 percent clear; TikTok and YouTube publish no numbers, but the same band works on both.
Below: what each platform actually documents, how big a caption should be on a phone, how many words belong on a line, and how to check the placement before the video goes out.
Why bottom-centre subtitles fail on vertical video
Bottom centre is the right place for subtitles on a television, a laptop or a YouTube video watched in the player. Nothing covers that part of the picture except the subtitles themselves.
A vertical feed is different. The platform draws its own layer over your video: the account name and the post caption at the bottom, a music or audio label, a column of buttons down the right edge, and a strip of controls at the top. A caption burned in at the traditional TV position lands underneath the platform's text, and two layers of white text on top of each other are unreadable.
The fix is not to make the caption bigger or bolder. It is to move it into the part of the frame the platform leaves alone. That part is smaller than the frame, and it is not the same on every platform, which is why the next section matters.
Safe zones on Reels, TikTok and Shorts
Only Meta publishes numbers. TikTok and YouTube describe what to avoid and leave the measuring to their templates and in-app guides.
| Platform | What the platform documents | Keep captions out of |
|---|---|---|
| Instagram and Facebook Reels | Meta's Reels ad guide: keep about 14% of the top, 35% of the bottom and 6% of each side free of text and logos | The top 14%, the bottom 35%, 6% at each side |
| TikTok | TikTok's ad specifications: no text where buttons, usernames and captions appear; a longer caption shrinks the safe zone | The right-hand buttons, the username and caption area at the bottom, the top strip |
| YouTube Shorts | YouTube's Shorts editor shows guides where the like button, comments, description and screen edges may cover an overlay | The right-hand buttons, the description at the bottom, the screen edges |
Meta's figures are the strictest of the three, which makes them a safe default when one video goes to every platform. Applied to a 1080×1920 frame, they work out to:
| Area | Meta's share | At 1080×1920 |
|---|---|---|
| Top strip to keep clear | 14% | about 269 px |
| Bottom area to keep clear | 35% | about 672 px |
| Each side to keep clear | 6% | about 65 px |
| Band left for captions | — | from about 269 px to 1,248 px down, 950 px wide |
Those pixel values are our arithmetic on Meta's percentages, not a separate Meta specification. Meta states its figures for Reels ads, but the profile icon, caption and buttons they protect against are the same on an ordinary Reel.
TikTok's own page adds one detail worth remembering for ads: the longer the caption you type into the post, the more of the bottom it covers, so a long description pushes the safe area up. Organic posts behave the same way. If you write long captions, give the subtitles more room than the minimum.
How big should subtitles be on vertical video?
About 4.5 percent of the frame height per line. That figure comes from the BBC's subtitle guidelines, which set an 8 percent line height for landscape video and multiply it by 9/16 for vertical video, so that text comes out at roughly the same size on both. On a 1080×1920 frame, 4.5 percent is a line height of about 86 pixels.
The same guidelines give two more numbers for 9:16 video:
- Up to three lines, against two for landscape. A narrow frame fits fewer words per line, so it needs one more line for the same sentence.
- About 25 characters per line, filling up to 90 percent of the frame's width. That is the vertical equivalent of the 37-character broadcast line.
Heavy social caption styles break these rules on purpose: one to three words at a time, much larger than dialogue subtitles. That works because each caption is on screen for less than a second and carries a word or two. For full sentences, such as an interview or a tutorial, the BBC's numbers are the safer starting point. The subtitle font guide covers the same sizing rule for landscape video and which fonts stay readable at that size.
How many words should go on a line?
As few as the reader can take in at a glance. Vertical video is watched on a phone at arm's length, often while scrolling, so the time a caption has to be read in is short.
Two styles work, and they are different jobs:
- Dialogue subtitles: one or two lines, up to about 25 characters each, broken at phrase boundaries. Keep the reading speed under the limits in the reading speed guide, because a phone screen does not make anyone read faster.
- Social captions: one to three words, highlighted as they are spoken. This is the style behind Hormozi-style captions and word-by-word karaoke captions, and it is built for muted autoplay rather than for long sentences.
Mixing the two in one video looks like a mistake. Pick one per video.
Where exactly should the caption sit?
Just above the bottom third, about two thirds of the way down the frame. That puts it below the speaker's face, which usually sits in the top half of a vertical shot, and above the platform's own text.
The BBC makes the same point for its own vertical video: it is common to place subtitles a little higher than in landscape, still in the lower third, because faces sit in the top half of the frame. The BBC's players have no feed interface on top, though. On Reels and TikTok the bottom third is already taken, so the caption moves to the top edge of it.
Two exceptions:
- Screen recordings and tutorials, where the action is low in the frame. Move the captions above the action, into the upper middle, and keep them out of the top strip.
- Videos with on-screen text, such as a product name or a title card. Never stack the caption on top of it; move one or the other.
How to check placement before you post
A caption that looks right in an editor on a desktop monitor can still land under a button on a phone. Check the export, not the timeline:
- Watch the rendered file on a phone, full screen, at normal viewing distance. If any line touches the right-hand buttons or the bottom text area, move it.
- Use the platform's own template. Meta offers a Reels safe-zone checker on its Reels ads page, TikTok links its safe-zone files from its ad specifications, and YouTube's Shorts editor draws its guides as you place text.
- Upload privately first where the platform allows it, and look at the post with the feed interface over it.
The burn-in is the expensive step, so check a short test render before rendering the whole video.
Placing subtitles for vertical video in Sablate
Sablate places captions in one of nine positions, with a margin measured from the top or bottom edge that can reach up to half the frame, so a caption can sit at any height. For Reels and TikTok, choose bottom centre and raise the margin until the lowest line clears the bottom third. The preview uses the same layout engine, font and margins as the burn-in, so the position you approve is the one that ends up in the video.
The 13 presets, including Reels, Hormozi and One Word, set the style. The Reels preset starts low in the frame, close to where TV subtitles sit, so raise its margin before you render for a feed. Then re-frame the export to 9:16 by cropping or by padding the sides with a blurred copy of the picture, which lays the captions out for the final frame instead of cutting them off afterwards, as the burn-in guide explains.
The free plan burns captions in, with a small corner mark, for videos up to ten minutes. Pro, a single $29 payment, removes the mark and the length limit. Download Sablate for Windows or Mac.
Which placement should you use?
"One video, posted to Reels, TikTok and Shorts." Meta's numbers: keep the top 14 percent and the bottom 35 percent clear and put the captions just above the bottom third. That clears all three interfaces.
"A talking head." Lower middle, under the chin, two lines at most.
"A screen recording or a tutorial." Above the action, in the upper middle, still clear of the top strip.
"An ad." Follow the platform's own template and preview tool for that placement. Ad reviews reject text in the marked areas, which ordinary posts are not checked for.
"Subtitles for YouTube's main player as well." Ship a separate subtitle file there, bottom centre, as described in the hardsub versus softsub guide. Captions placed for a feed sit too high in a landscape player.
The short version
On vertical video, subtitles go in the lower middle: below the face, above the bottom third that the platform covers with its own text and buttons. Meta's 14 percent top and 35 percent bottom margins are the only published numbers and work on all three platforms. Size each line to about 4.5 percent of the frame height, keep to two or three short lines, and check the export on a phone before you post it.
Frequently asked questions
Where should subtitles go on Instagram Reels?
Above the bottom third and below the top strip. Meta's ads guide for Instagram Reels recommends keeping roughly the top 14 percent, the bottom 35 percent and 6 percent on each side free of text, because the profile icon, caption and buttons cover those areas. On a 1080×1920 video that leaves the band from about 270 to 1,250 pixels down.
Where should captions go on TikTok?
Clear of the buttons on the right and the username and caption at the bottom. TikTok's ad specifications publish no fixed margins; they say text must not sit where buttons, usernames and captions appear, and that a longer caption shrinks the safe area. Keeping the bottom 35 percent clear, as Meta advises for Reels, works on TikTok too.
Is there a safe zone for YouTube Shorts?
Yes, but YouTube shows it rather than publishing numbers. When you place text in the Shorts editor, guides appear where the like button, comments, description and screen edges could cover it. For captions burned in somewhere else, the same middle band that works for Reels and TikTok keeps them clear of the Shorts interface.
How big should subtitles be on vertical video?
About 4.5 percent of the frame height per line. The BBC derives that figure from its 8 percent rule for landscape video, so captions look the same size in both. On a 1080×1920 video that is a line height of about 86 pixels, with at most three lines of roughly 25 characters each.
Should subtitles be at the top or the bottom of a vertical video?
In the lower middle, not at the very bottom. Faces usually sit in the top half, so captions belong below them, but the bottom third of a social feed is covered by the platform's own text and buttons. Aim for the band just above it, about two thirds of the way down the frame.