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Opus to VTT

Opus to VTT, voice recordings to web captions

Turn an Opus audio file into a VTT (WebVTT) caption file on your own computer. SnailText transcribes the speech and writes the VTT with phrase-level timing - no upload and no per-minute billing.

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Generate VTT locally, nothing uploaded

No account · Nothing uploaded

Convert Opus to a VTT caption file

Opus is a modern open-source codec used by WhatsApp voice messages, Discord, Matrix, and many VoIP and podcast tools. VTT (WebVTT) is the caption format HTML5 video players accept natively. SnailText reads the Opus audio, transcribes the speech with the Whisper model, and writes a phrase-level VTT, all on your machine.

You get a separate .vtt file ready to reference in an HTML5 player or upload to a streaming platform. Opus works immediately with no extra codec download.

How to convert Opus to VTT

  1. Open the Transcribe files screen in SnailText.
  2. Add your Opus audio file (or a folder of them).
  3. Choose VTT as the output before you run it.
  4. Run it. The .vtt file is saved next to your audio.

Try it on your own files

Download for Mac

Generate VTT locally, nothing uploaded

Opus to VTT free, without uploading the file

Online converters upload your Opus audio to a server. SnailText does it locally: the file stays on your machine, there is no length limit, and the free tier has no watermark.

If you need SRT instead of VTT, the Opus to SRT page covers that. SnailText exports both, you just pick before the run.

Opus to VTT FAQ

How do I convert an Opus file to VTT?
Install SnailText, open Transcribe files, add your Opus file, choose VTT as the output, and run it. It generates the VTT locally with the Whisper model, no account and no per-minute charge.
Can SnailText make VTT captions from a WhatsApp voice message?
Yes. Export the WhatsApp voice message as an Opus file, add it to SnailText, choose VTT as the output, and run it. The VTT is generated locally, nothing is uploaded.
What is the difference between Opus to VTT and Opus to SRT?
VTT (WebVTT) is the web-native format for HTML5 video and streaming platforms. SRT is older and more widely supported in media players and editing tools. SnailText generates both, you pick before the run.
Will the subtitles be burned into the video you pair the OPUS with, or is the VTT a separate file?
No. SnailText writes a separate VTT file and does not hardcode captions into the video. That keeps the subtitles editable and lets you attach them in any player or editor. If you want them burned in, overlay the file in a video editor afterward.

More ways to transcribe and caption

All formats

Audio to VTT →

Turn any audio recording into a WebVTT caption file on your own computer, with no upload and no per-minute billing. If you know your format, there is a dedicated guide for it - links below.

Same format, other output

Opus to SRT →

Related formats

Subtitle hubs

All transcription formats →

Generate a VTT from your Opus

Free local subtitle generation, no account needed. VTT files on Mac and Windows.

Download for Mac Or for Windows →