Edit video without uploading your file
FinalCap is a private AI video editor that runs in your browser. You describe the edit in plain English, the AI returns a structured tool call, and FFmpeg in your browser runs it on your device, so the video file is not uploaded for normal edits.
Opens FinalCap with "Resize this video to 9:16 and add captions" ready in the chat box. Editing your own video needs a Google sign-in and a FinalCap subscription, and nothing runs until you press Send. The sample clip needs neither; it is an animated short with music and no dialogue or vocals, so use it to see how chat editing works rather than to test captions.
How to do it in 3 steps
Open your video
Sign in with Google and open a video file from your computer. Opening the file does not upload it; the browser reads it from your device.
Describe the edit in plain English
Type one of these prompts, or your own wording:
- Resize this video to 9:16 and add captions
- Trim the first five seconds and boost the saturation
- Make it 2x faster and convert it to WebM
Check and download
FFmpeg renders the edit in your browser. Play the result in the editor, then download the finished file.
What you can control
- Trim, cut and join clips, with transitions between them.
- Resize and crop to 9:16 for Reels, TikTok and Shorts, 1:1 for feeds, or 16:9 for YouTube.
- Captions transcribed on your device, burned in or exported as SRT and VTT files, with translation if you ask for it.
- Speed, volume, fades, loudness, color, text overlays, rotation and format conversion to MP4, WebM, MOV or MKV.
What runs on your device, and what goes to our server
- For normal edits your video file is not uploaded. Edits run with FFmpeg compiled to WebAssembly in your browser, and captions are transcribed by default with a Whisper speech model that also runs in your browser.
- To plan an edit, the AI receives your typed request and up to four small still frames from the video, never the video file itself.
- Translating captions sends only the caption text to the server. Lyric captions send only the audio track, and only after you agree.
- If a step cannot run in your browser, FinalCap asks before uploading anything to do it on the server. The default answer is no.
Details: FinalCap privacy policy.
FAQ
Does FinalCap upload my video?
No, not for normal edits. The video file stays on your device and FFmpeg runs the edit in your browser. FinalCap asks for explicit confirmation before any media upload, and the only routine exception is lyric captions, which send the audio track (never the video) after you agree.
What does the AI see?
Your typed request and up to four small still frames from the video, so it can plan the edit. It never receives the video file, and it can only choose from the edits FinalCap knows how to run, with the parameters those edits accept.
How do captions work without uploading?
A Whisper speech model downloads once, runs in your browser (WebGPU or WebAssembly) and transcribes the audio on your device. Translating the captions sends only the caption text to the server.
What if an edit cannot run in my browser?
FinalCap asks before uploading anything to do that step on the server. If you say no, the edit does not run that way; for captions you can take the SRT and VTT subtitle files instead of a burned-in video.
Is FinalCap free?
It is free to try: the sample video works with no sign-in and no subscription. Editing your own videos needs a Google sign-in and a FinalCap subscription, and nothing runs until you press Send.