Burn-in captions for Reels and TikTok
Feeds do not enable a sidecar. Burn-in is the format for Reels, TikTok and Shorts. YouTube long-form can take an SRT.
Reels, TikTok, and Shorts do not play your .srt. The feed autoplays muted and never enables a sidecar the viewer did not ask for. Burned-in captions are the format those surfaces actually show: pixels in the file. YouTube long-form can take an SRT. Do not ship one object to all four.
The feed will not enable a sidecar
Closed captions are a track the player draws. The viewer can switch them off. The platform skins them. That is the right object for a course player and for YouTube landscape, where someone sat down, may unmute, and may hunt a CC button.
A muted autoplay session is none of those things. The impression starts on a silent frame. If the claim is only in a sidecar, the claim is not in the impression. Instagram Reels, TikTok, and YouTube Shorts all default that way. Native “auto captions” on those apps are a player overlay the viewer can ignore and the algorithm does not treat as your art. They are also not your type, your placement, or your timing.
Burn-in is the delivery, not a style preference. Speech is transcribed, aligned, styled, and composited onto the frames. After that, re-upload, re-encode, and a platform with no caption system still show the words. That is why short-form went to open captions and stayed there.
The AI caption generator is that path. It does not write a sidecar and hope the feed attaches it. If a client also wants an archive track, export the transcript separately and convert with the VTT to SRT converter. That file is for YouTube long-form and for the edit. It is not the Reel.
Platform by platform
TikTok. In-feed playback is 9:16, muted until the viewer unmutes. There is no caption file you attach that the For You page will reliably draw as your design. Burn the line into the MP4. Keep it out of the username, caption field, and right-rail buttons. TikTok’s own auto-captions can still appear on top of your burn if the viewer has them on — another reason to keep your block compact and in a band the chrome does not own. Do not upload a silent cut plus an SRT and call the job done.
Instagram Reels. Same mute-autoplay physics. Reels does not treat an SRT as the in-feed caption. Stickers and the native caption toggle are not your timed transcript. If the hook is speech, burn it. If the hook is a line nobody said, that is an overlay, also burned. Paid Reels add a CTA bar; recheck placement on the paid crop, not only on the organic file.
YouTube Shorts. Still a 9:16 mute-first feed. Burn-in is the format. YouTube will also draw its own chrome, and as of 27 May 2026 the YouTube Blog puts a photoreal / meaningfully AI-altered label on the Short as an overlay (Improving AI labels for viewers and creators). That overlay is extra furniture on the picture. Keep captions out of the bottom band and out of that label zone. Labels alone do not affect recommendations or monetization eligibility, per that post. They do cover type.
YouTube long-form. This is the exception that keeps getting collapsed into the short-form rule. Landscape YouTube has a player, a CC button, and an ingest path for SRT or the platform’s own caption asset. Closed captions are correct here: searchable, restylable, language-swappable without a re-render. You can still burn-in if the look is part of the show. You should not only burn-in if you also need a second language or a deaf-and-hard-of-hearing track you expect the player to toggle. Upload the sidecar. Do not paste the Reel file into a 12-minute slot and call the captions done.
Everywhere else that is still a feed. Kick clips, Reddit video, in-app stores that autoplay muted — same rule as TikTok. If the surface will not enable a track, the words have to be in the picture.
What to burn, and what to keep as a file
Burn after picture lock. Pixels do not ripple when you trim. A recut is a recaption.
Transcribe in the language that was spoken. add_veed_captions supports 165 language codes. It does not translate. A Spanish Reel with the code left on en-US is a bad English transcript on a mute feed.
Pick the look for the surface, not for the archive. BASIC (21 presets at 1×) for a quiet, readable block. DYNAMIC (9 presets at 2×) when the organic hook is a spoken phrase and the mute pass is still readable. Preview on the first seconds of this 9:16 file. Contrast is against this plate, under this chrome.
Place for the chrome that will actually sit on the upload, not for the editor’s full frame. Safe area is a snapshot. Recheck. Essential type out of the bottom ~200px on a 1080×1920 export is a working default, not a contract. Shop tabs and longer usernames grow the band.
Keep a sidecar when a destination can use one. Long-form YouTube, a course, a broadcast master, a client who will restyle. The add captions path burns. The transcript export is the sibling, not a substitute for the Reel.
EU-facing realistic synthetic media still needs a mark at first exposure under Article 50. That mark is not a subtitle cue. Put it in the first frame or the first second of audio, then caption the speech as you would any other cut.
Do not twin the format argument
This page is delivery. The format definition — pixels versus a .srt / .vtt sidecar, what each can and cannot do — is a different post. The production rule here is smaller:
- Reels: burn-in.
- TikTok: burn-in.
- Shorts: burn-in, and leave room for YouTube’s own overlay.
- YouTube long-form: SRT (or VTT) is available; use it. Burn-in only if the look is the show.
Getting that matrix backwards is a quiet, expensive miss. Burning three language versions of a 12-minute YouTube because someone copied the Reel pipeline is a week of re-renders. Shipping a perfect SRT with a silent TikTok is a caption job that never appeared on the For You page.
One 9:16 file can serve Reels, TikTok, and Shorts if the type clears all three chromes. That is a placement check, not a reason to attach a sidecar. The sidecar is for the room with a player.
Burn the next Reel or TikTok in Versely.
FAQ
Will TikTok or Reels play my SRT in the feed?
No. Mute autoplay will not enable a sidecar. Burn the words into the MP4. Keep an SRT for YouTube long-form and for the archive.
Do YouTube Shorts work like long-form captions?
No. Shorts are a mute-first vertical feed. Burn-in is the format. Long-form can take a closed track under the player. As of 27 May 2026, photoreal AI Shorts also carry an on-video overlay — keep type out of that zone.
Can one burned file go to Reels, TikTok, and Shorts?
Yes, if the type clears each platform’s chrome, including Shorts’ AI overlay when that label applies. Recheck placement. Do not assume the organic TikTok safe band is empty on a paid Reel or a labelled Short.