How to Add Auto Captions to TikTok/Reels/Shorts for Free
Add auto captions to TikTok, Instagram Reels, and YouTube Shorts for free. AI-generated subtitles, no watermark.
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MiOffice AI is an AI-powered digital workspace studio. Create, edit, convert, compress, collaborate, and share — video, audio, images, documents, scanning, notes, screen sharing, and file transfer. 150+ applications, all in one place.
Why Captions Matter for Short-Form Video
85% of Facebook and Instagram videos are watched without sound. On TikTok, captioned videos see 40% more watch time on average. Captions are not optional for short-form content — they are essential for reach, engagement, and accessibility.
MiOffice Auto Captions uses Whisper AI on GPU servers to transcribe your audio and burn styled captions directly into the video. No watermark, no account, no subscription.
How to Add Auto Captions with MiOffice
- 1
Record or Upload Your Video
Record your TikTok, Reel, or Short, then go to the Auto Captions tool. Upload MP4, MOV, WebM, or AVI.
- 2
AI Transcribes Your Audio
Whisper AI processes your audio on GPU servers, generating accurate word-level timestamps. Files are deleted immediately after processing.
- 3
Customize Font and Position
Choose font size and position (top or bottom). Place captions at the bottom third for TikTok or top for Reels — whatever fits your style.
- 4
Download and Post
Download your captioned video as MP4 — no watermark. Upload directly to TikTok, Instagram, YouTube, or any platform.
MiOffice vs CapCut vs Kapwing vs Veed.io
| Feature | MiOffice AI | CapCut | Kapwing | Veed.io |
|---|---|---|---|---|
| Auto Captions | Whisper AI | Built-in | Built-in | Built-in |
| Watermark | No | No | Yes (free tier) | Yes (free tier) |
| Price | Free to try | Free | $24/mo | $18/mo |
| Signup Required | No | Yes | Yes | Yes |
| Privacy | Deleted immediately | ByteDance servers | Cloud storage | Cloud storage |
| Platform | Web (any device) | Web + mobile | Web only | Web only |
Platform-Specific Sizing
TikTok (9:16)
1080 x 1920 pixels. Place captions in the bottom third, avoiding the comment and share button area on the right side.
Instagram Reels (9:16)
1080 x 1920 pixels. Keep captions above the bottom 250px to avoid being covered by the username, caption text, and music label.
YouTube Shorts (9:16)
1080 x 1920 pixels. Captions work best centered or in the lower third. Avoid the subscribe button and title area at the bottom.
Facebook Feed (1:1)
1080 x 1080 pixels. Square format for feed posts. Center captions vertically for best readability in the scroll feed.
Privacy & Security
- --Processed on secure GPU servers. Your videos are processed on dedicated GPU infrastructure and never stored permanently.
- --Deleted immediately after processing. Video files are purged from server memory as soon as you download the captioned result.
- --No content analysis. We do not review, categorize, or use your video content for any purpose beyond caption generation.
- --Encrypted transfer. All uploads and downloads use HTTPS/TLS encryption.
Frequently Asked Questions
Can I add auto captions to TikTok videos for free?
What video formats and sizes are supported?
Do the captions have a watermark?
How accurate are the AI-generated captions?
Jay Padimala
CEO & Founder
Jay Padimala is CEO and Founder of MiOffice, a product of JSVV SOLS LLC.
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