Most short videos are watched with the sound off, so captions decide whether people stay. There are two ways to add them, and a few rules that make them readable on a phone.
Option A: the app’s auto captions
TikTok, Instagram, YouTube and CapCut all generate captions. Fast and free, but:
- the text stays inside that app, you cannot easily reuse it elsewhere,
- accuracy outside English varies,
- editing many mistakes on a phone is slow.
Option B: make a subtitle file first
Create an SRT or VTT from the video, fix it once on a computer, then reuse it everywhere: YouTube and Facebook accept SRT directly; for TikTok and Reels you import it in your editor or burn the captions into the video.
Our auto subtitle generator makes SRT, VTT and TXT from a video in 60+ spoken languages, with optional translation so the same clip can reach other languages. Free minutes when you verify your email, then pay per minute, no subscription.
Word-by-word animated captions
The highlighted, word-by-word style that is popular on Shorts and Reels can be made with animated captions: it turns the speech subtitles into a captioned video ready to post.
Rules for readable captions on vertical video
- Short lines: 1 to 2 lines, a few words each.
- Stay above the bottom UI: the caption, buttons and description cover the lowest part of the screen. Put captions in the middle third.
- High contrast: white text with a dark outline or box.
- Check names and numbers: these are the mistakes viewers notice and comment on.