Add captions to any video. Free, automatic, animated.
Upload your clip. AI transcribes the audio with word-level timing, burns in animated captions, and gives you a TikTok-ready MP4. No editing, no manual sync, no subscription.
Upload your video
Caption style
Cost: 2 credits
Sign in required to generate. Free credits included on signup.
From upload to captioned MP4 in under 2 minutes
Three steps. Zero editing knowledge required.
Upload your video
Drop in an MP4, MOV or WebM up to 500 MB. Any aspect ratio — vertical, horizontal, square.
AI transcribes the audio
OpenAI Whisper transcribes the speech with word-level timestamps. Auto-detects the language.
Get captioned video
Animated captions burned into your video. Download as MP4, post anywhere.
Built for short-form creators
85% of social video is watched on mute. Animated captions are how you keep eyeballs through the first three seconds.
Under 2 minutes
Most clips finish in 30 – 90 seconds. Whisper transcribes, Remotion renders, you download.
30+ caption styles
TikTok yellow, MrBeast green-yellow-red, Hormozi block, minimal white — all the styles that actually perform.
30+ languages
Auto-detects English, Spanish, French, German, Portuguese, Japanese, Mandarin, and more.
Word-level accuracy
OpenAI Whisper gives 95%+ accuracy on clear audio. Captions sync to the exact word.
No watermark
Output is a clean MP4 ready to publish anywhere. Free tier — no watermark.
Beyond captions
Same account also generates videos from scratch — UGC ads, faceless content, AI characters.
Ready to caption your first video?
Sign up free. Free credits to get you started.
Try it nowFAQ
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Why animated captions matter for short-form video
Roughly 85% of social video is watched on mute. Without captions, your hook lands in silence. Animated word-by-word captions — popularized by tools like SubMagic and creators like MrBeast — keep viewers engaged through the first three seconds, which is where most TikToks and Shorts die. This tool gives you the same effect, automatically, in under a minute.
How to add captions to a video automatically
Upload your video file (MP4, MOV, or WebM). The AI transcribes the audio using Whisper, producing word-level timestamps. You pick a caption style — bold yellow TikTok style, MrBeast-style colored highlights, minimal white, or one of nine other presets. The captions are burned into the video using the same Remotion engine that powers StoryShort's native AI video generation. Download the result, post it anywhere.
Works for TikTok, YouTube Shorts, Instagram Reels
The tool preserves your original aspect ratio. Upload a 9:16 vertical for TikTok and Reels, 16:9 horizontal for YouTube long-form, or 1:1 square for feed posts. The captions auto-position to avoid covering faces or important visual elements.
Caption styles built for engagement
Every preset is designed around what actually performs on social. Classic SubMagic-style yellow-on-black for high contrast. MrBeast-style with rotating word colors. Minimal mode for branded content. Pop-bounce animations for high-energy clips. All presets include word-level highlighting that times perfectly with the speaker.