Auto captions for TikTok and Shorts, with AI
Mid-screen, clear of what TikTok covers, with the spoken word in yellow. On your PC, no watermark.
Updated: October 2026 · 6 min read
To add captions to a TikTok or a Short for free with AI on your PC: install AppGrabbit, open Download › Subtitles with AI, paste the link or drop the mp4 from your phone and click Get subtitles. Pick the Center style on a real frame (free): three or four large words mid-screen, the spoken one in yellow, away from what the interface covers. Make the video leaves you the 1080×1920 MP4 with no watermark. 1 credit · burning: Pro
What TikTok covers and where captions should go
On TikTok, the description, the sound name and the progress bar cover the bottom of the video, and the like, comment and share buttons cover the right edge. It is the classic trap: almost every editor puts captions at the bottom, exactly where they cannot be seen. That is why the videos that work carry the text mid-screen, large, with the spoken word highlighted: people watch muted and read.
The safe zone, in numbers (1080×1920)
- TikTok — the interface covers about 320 to 660 pixels at the bottom (17 to 35 % depending on the screen) and 120 to 300 on the right edge, where the buttons sit.
- Instagram Reels — covers 35 % at the bottom, 14 % at the top and 6 % on each side.
- Where each of our styles sits — Center is drawn mid-screen: always safe. Classic and Box move up 15 % from the bottom in portrait: on TikTok that can still fall inside what the interface covers, so for TikTok and Reels pick Center.
TikTok's native captions versus burned-in subtitles
TikTok generates automatic captions when you post, and they are good for accessibility. But they live inside TikTok: they do not travel with the video if you save it, post it to Shorts or send it on WhatsApp. Burned-in subtitles stick to the video wherever it goes, in the style you chose, and they are the ones that keep people watching: the eye follows the lit word. The honest part: burned-in captions cannot be turned off; if someone wants them in another language, there is no button.
AppGrabbit against the other ways
| AppGrabbit | TikTok captions | CapCut | Phone apps | |
|---|---|---|---|---|
| Travel with the video to Shorts, Reels, WhatsApp | ✓ Yes, burned in | ✗ TikTok only | ✓ Yes | ✓ Yes |
| Lit word mid-screen | ✓ Center | ✗ No | ✓ On Pro | ~ Some |
| Your video never leaves your PC | ✓ Never | ✗ Lives on TikTok | ~ Depends on the version | ✗ Goes to their cloud |
| Watermark | ✓ Never | ✓ No | ~ By feature | ✗ On free |
| Cost | Get subtitles: 1 credit (5 free a month) · preview: free · Make the video: Pro $8.99/mo or 7-day pass $3.99 | Free, inside TikTok | Auto captions on Pro, about USD 20 a month | Weekly subscription |
Step by step
- 1Install AppGrabbit for Windows — Download the free installer (everything included). Windows will say it protected your PC because the installer is not code-signed: click More info, then Run anyway.
- 2Bring the video in — If it is already on TikTok, paste the link: the app downloads the full video without TikTok's watermark. If it is yours and not posted yet, drop the mp4 from your phone.
- 3Click “Get subtitles” (1 credit) — The first time, the app gets the AI engine ready on your PC (a one-time download) and carries on by itself. Out come the .srt, the .vtt and the .txt in the Subtitles folder, timed word by word.
- 4Pick Center — For TikTok and Shorts, the Center style: three or four large words mid-screen, the spoken one in yellow. It stays clear of what TikTok's interface covers (bottom and right).
- 5Click “Make the video” (Pro or the 7-day pass) — The subtitles are burned into the video, at its size and with no watermark. The MP4 is named after your video plus “_subtitulos” and lands in the Library.
- 6Post it to TikTok or Shorts — The MP4 comes out 1080×1920 if your video was portrait, H.264 with AAC audio: what both platforms ask for. If you also want closed captions, the .srt works on YouTube.
Frequently asked questions
Yes, inside TikTok: they are generated when you post and edited there. But they live on TikTok: if you download the video or post it to Shorts, Reels or YouTube, they do not travel. Burned-in subtitles go wherever the video goes.
Because TikTok's interface covers the bottom (description, music, progress bar) and the right edge (the buttons). Center is drawn mid-screen, in the clear. Classic and Box move up 15 % in portrait, and on TikTok that can still be covered.
Same thing: same 9:16 format, same covered area at the bottom, same Center style. The MP4 that comes out works for both without touching anything.
Yes, the original video. But subtitles only make sense on your own videos or with permission: do not post someone else's video to your account.
Getting the subtitles (.srt, .vtt and .txt) costs 1 credit; Free comes with 5 a month. Previewing them on your video, in the three styles, is free. Burning them in (“Make the video”) is for Pro (USD 8.99 a month) or the 7-day pass (USD 3.99, no renewal). There is never a watermark, not even on Free.
The spoken one; the engine detects it and you can pin it before starting. It does not translate: a video in another language is a different job.
The app tells you and gives the credit back. A music-only video gets no made-up text.
Nothing. The video stays on your PC: the AI engine (Whisper, whisper.cpp) runs on your computer, on your NVIDIA card if you have one or on the CPU if not, and FFmpeg burns the subtitles right there.
Safe zone sources: TikTok, Instagram and Facebook safe zones (House of Marketers) · Safe zones for TikToks and Reels (Ignite Social Media)
Related guides
Captions for your TikTok, on your PC
Windows 10/11 · Get subtitles: 1 credit, 5 free a month · Make the video: Pro or 7-day pass