Auto Caption Generator
Add animated captions to any video — automatically. Upload a clip, auto-generate captions, pick a style, and export a captioned MP4 right in your browser. Free for your first 5 videos. No install, no watermark.
Free Online Auto Caption Generator
The fastest way to add captions to a video
Caption X automatically generates captions from your video and burns them in for you — no manual typing, no timeline, no install. It's built for short-form creators who want bold, animated captions that boost watch time on TikTok, Reels and YouTube Shorts.
Why creators use it
Auto captions in seconds — the AI transcribes your speech and times every line.
Animated, scroll-stopping caption styles, not plain subtitles.
Everything runs in your browser, and your video never leaves your device.
How It Works
Add captions to your video in four steps
Step 1
Upload your video
Drop in an MP4 or MOV (up to 10 minutes). Your video stays on your device — only the audio is sent to generate the captions.
Step 2
Auto-generate captions
AI transcribes the speech with word-level timing in 50+ languages, then groups it into clean, readable caption lines automatically.
Step 3
Style your captions
Pick an animated caption template, then fine-tune color, size, position and pop/blur animation. Review and edit any line before exporting.
Step 4
Export a captioned MP4
Captions are burned into your video and downloaded instantly — no watermark. You can also export an SRT subtitle file.
Best Use Cases
Captions for TikTok, Reels, YouTube Shorts and more
Generate captions once and export a captioned MP4 you can post anywhere. Because the captions are burned in, they display on every platform — no re-uploading subtitle files.
TikTok, Reels & Shorts
Add bold, animated captions that keep viewers watching to the end — the look that performs on short-form video.
Podcasts & interviews
Turn talking-head clips into captioned social posts so people can watch with the sound off.
Accessibility & reach
On-screen captions make your videos watchable in any feed and accessible to more viewers.
Creators & marketers
Get fast, on-brand captions without opening CapCut or Premiere — straight from your browser.
FAQ
Auto caption generator — frequently asked questions
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