Why this tool is useful
Generate WebVTT captions for an owned audio or video clip locally, preserving the recording on your device throughout recognition.
Local File Tools · runs locally
Private Audio to WebVTT Caption Maker
Generate WebVTT captions for an owned audio or video clip locally, preserving the recording on your device throughout recognition.
Ready. Your working data stays in this browser.
Files and capture streams stay on this device. Processing uses browser APIs only; nothing is uploaded to YTSave, the media API or a proxy. No server copy is created, stored or left to delete. The file picker is cleared when processing starts, and disposable worker memory is destroyed after completion or cancellation. Preview and generated-output memory is released when you clear the tool or leave the page.
How it works
The browser runs multilingual speech recognition against a self-hosted quantized model and converts its checked timestamp chunks into a WEBVTT document with dot millisecond timing.
Practical example
Open a short lecture recording, choose a language only when detection needs help, proofread the cues, and save VTT captions for an HTML video player.
Validation
The calculation is deterministic and explains validation errors instead of silently changing invalid input.
Privacy boundary
Input and output remain in this tab. Copy and download happen through browser APIs without a server upload.
Result passport
Every run reports its tool mode, timestamp and input/output size so transformed data can be audited.