Privacy by architecture
Your video stays with you.
Most editors upload your whole file before they can do anything. capshak decodes, previews and encodes in the browser. To write captions, it sends only a compressed audio track, about 240 KB a minute. Backup to our servers is your choice, so you can open a project on another device.
- Decode & preview
- Waveform & timeline
- Effects & grading
- H.264 export
- Transcription
- Translation & proofreading
- Optional backup
Step by step
Your video’s path, from picking the file to export
- 01
Opened on your device
When you pick a file, the browser decodes it with WebCodecs. Preview, waveform and filmstrip are all built on your device, and a copy stays in browser storage (IndexedDB).
- 02
Only audio for captions
To make captions, the browser turns the soundtrack into a mono 32 kbps Opus file and sends only that. The server passes it to the speech-to-text service and does not keep the audio.
- 03
Text for translation and proofreading
Translation and proofreading receive caption text only. The AI editor looks at a few small preview frames only when you ask it to.
- 04
Effects and export on your GPU
Color, effects, transitions, layers and H.264 encoding all run in the browser. The final MP4 is saved straight to your device.
- 05
Optional backup
If you want to open a project on another device, the video is backed up in the background and deleted automatically after a set time. It plays only through short-lived signed links.
Your next video, captioned in minutes.
Edit and export for free, and pick a plan when you want AI captions. Nothing to install.
- Monthly or yearly plans, in toman
- Your video stays on your device
- Persian and English