SRT vs burned-in captions for Reels, Shorts and TikTok

SRT (SubRip) is a plain-text subtitle format: a numbered list of entries, each with a start time, an end time and the words to show. It is a separate file that travels alongside the video. Burned-in captions are drawn into the frames, so they are part of the picture.

W3C's accessibility guidance draws the same line: most captions are “closed”, meaning viewers can show or hide them, while “open” captions are always displayed and cannot be turned off. An SRT file gives you closed captions where a player supports them; burned-in captions are open captions.

An SRT entry looks like this (a format example, not an export):

1
00:00:00,000 --> 00:00:01,800
First caption block

2
00:00:01,800 --> 00:00:03,200
Second caption block

Use burned-in captions when the look of the captions is part of the video, or when you cannot rely on a platform to show a caption file. For short vertical video that is usually the case.

• Animated, word-by-word captions can only be burned in. An SRT file carries words and timing, not colours, fonts or motion.
• They travel with the file. The captions look the same wherever the video is played or shared, because they are part of the picture.
• No platform feature is involved. Nothing has to accept, convert or display a separate file.

The costs are real. Viewers cannot switch burned-in captions off, and a typo means re-exporting and uploading again, so read the preview through before you export. Keep the words inside the area the app interface leaves clear: CutXflow's preview has a grid button that shows a Reels and Shorts safe-zone guide. And if a platform also generates its own captions from your audio, check the caption settings for the post so viewers do not see two sets of words.

Use an SRT file when you want captions that viewers can turn on and off, when you want to keep editing the text elsewhere, or when the platform you are posting to accepts caption files and the video is mostly about the picture and the sound rather than the captions.

YouTube is the platform to check first. Its help page describes adding subtitles in YouTube Studio by choosing Upload file and then either With timing or Without timing, and an SRT already contains its timings. YouTube's list of supported formats (opens in a new tab) includes SubRip (.srt), with three conditions: only basic versions of the file are supported, no style information is recognised, and the file must be plain UTF-8. So YouTube gets your words and timing, and none of a styled caption's colours or animation. The upload steps are on YouTube's add-subtitles page (opens in a new tab), which describes videos in general and does not single out Shorts.

Instagram and TikTok publish their own caption guidance (Instagram Help Center: closed captions for reels (opens in a new tab); TikTok Support: captions (opens in a new tab)). This guide does not rely on either platform's handling of an uploaded caption file, so check those pages before you plan around one.

The SRT follows the same caption blocks as the burned-in video, so line breaks match between the two. It has no colours, fonts or animation, because the format has nowhere to put them. Open the file in a text editor and skim it before you upload it, as you would with any generated subtitle file. Exporting needs a browser that supports WebCodecs; desktop Chrome or Edge is the safest choice, and the FAQ lists the others.

Yes, but not on the same video in the same place, or a viewer who switches captions on will see the words twice. For Reels and TikTok, post the burned-in MP4. For a longer YouTube video, either upload the burned-in MP4 and skip the SRT, or upload your original clip with no captions and attach the SRT.

• You want an animated, styled look: burned-in.
• You want viewers to control the captions, or you expect to edit the text later: SRT, on a platform that accepts it.
• You are posting the same file to several apps: burned-in, because it does not depend on any one of them.
• You are not sure: burned-in is the safer default for Reels, Shorts and TikTok, since it does not depend on a platform feature.