Opus to text
Transcribe an Opus file, such as a WhatsApp or Telegram voice note, to text you can copy or download. Free, with no upload.
Drop an Opus file or voice note to transcribe it
The speech is recognized on your device, so nothing is uploaded and there's no limit on length.
MP3, M4A, WAV, FLAC, and other audio, or a video with sound.
How to convert Opus to text
WhatsApp on a phone saves voice notes as Opus files, which most apps won't even play. Open one here and Mastershot writes down what's said, in paragraphs, with times if you want them. Copy the text, or save it as a TXT, SRT, or VTT file. The voice note is transcribed in your browser, so nobody else hears it.
Step 1
Choose your Opus filePick a voice note or other recording.Step 2
Transcribe itThe speech is written down on your device.Step 3
Copy or downloadSave the transcript as TXT, SRT, or VTT.
What to expect
- Supported inputs
- Opus files (.opus, .ogg, .weba), including WhatsApp and Telegram voice notes, and any other recording or video this browser can read.
- What happens
- Whisper, a speech recognition model, listens to the voice note on your device and writes down each word with its time.
- Limits
- The first time, the browser downloads the 77 MB speech model and keeps it. After that, a one-minute voice note takes about ten seconds. Voice notes are recorded at a low quality, so a noisy street or a far-away phone makes more mistakes.
Private by design
Your video stays on your device
Mastershot processes your file locally in this browser. It does not need to be uploaded to a server, and you do not need an account to use the tool.
- No upload
- No signup
- No watermark