Online Subtitle Generator — Local AI Speech-to-Text (Whisper)
Generate SRT and VTT subtitles for audio or video with local Whisper speech recognition. The AI model runs in your browser — files never upload.
Try it Now →Why Choose Formavide?
- Privacy First: All tools run locally in your browser — files are never uploaded.
- No Sign-Up: Open your browser and start. No account needed.
- Free to Use: Basic features are always free.
- Cross-Platform: Chrome, Edge, Safari, and mobile.
How to Use
- Upload an audio or video file (MP3, WAV, M4A, MP4, WebM and more).
- Pick a model — Whisper Base is faster, Whisper Small is more accurate.
- Click start. Recognition runs locally in your browser (model downloads on first use).
- Preview and edit the subtitles, then export as SRT or VTT.
FAQs
How fast is the transcription?
It depends on your device. Browsers with WebGPU get GPU acceleration automatically; otherwise it falls back to CPU, which is slower.
Is my audio private?
Yes. The Whisper model runs in your browser — audio never leaves your device.
Why is there a model download on first use?
The Whisper model is fetched from a public CDN (Base is smaller and faster to download; Small is larger and more accurate) and cached by your browser afterwards.
Which languages are supported?
Language auto-detection is on by default, with manual Chinese/English override, based on the Whisper model.
Can I burn subtitles into the video?
The current version exports SRT/VTT subtitle files; burned-in captions are not supported yet.
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View all tools →All tools run locally in your browser — files are never uploaded.