Automatic Format Conversion: You Don't Need to Convert Anything
How VoxScriber automatically converts uncommon formats and extracts audio from videos on the server, at no extra cost and without any action from you.
Golden rule: send the file as it is. If the format isn't one of the native ones, the platform converts it on its own on the server before transcribing — no extra cost, no installed software, no action on your part.
What is converted automatically
- 29 less common audio and video formats — from
.aiffand.alac(Apple) to professional video formats like.mxf,.prores, and.braw— are converted to MP3 before transcription; - Videos (MP4, MOV, MKV, AVI...): the audio track is extracted on the server; the image isn't used;
- Native formats (MP3, WAV, M4A, OGG, FLAC...) go through directly, without conversion.
The full list is at Accepted formats and limits.
How it works under the hood
Deep validation
Every file goes through a technical scan that confirms there's a real audio track and measures the exact duration (that's what defines the cost in cycles). Files with an incomplete header — such as WhatsApp audio and browser recordings — get a second, tolerant pass before any rejection.
Conversion to MP3
When necessary, the file is converted to MP3 on the server. The converted file is used only for transcription — the process is transparent to you.
Transcription
The engine receives the audio already in a format it understands. Some engines natively accept fewer formats (the Standard one, for example, works with a set of ~10) — the upfront conversion covers the difference without you noticing.
Conversion doesn't cost cycles. The transcription cost is calculated from the audio duration and the chosen engine — converted or not, the price is the same.
Automatic conversion doesn't fix broken files: if the file is corrupted or is an HTML page saved with an audio name, it's rejected during validation. See Common upload issues.
When converting BEFORE might be worth it
Only in one scenario: slow internet + huge file. A 2 GB video becomes an MP3 of ~100 MB if you extract the audio locally before uploading — the transcription result is the same, but the upload is 20× faster. For normal connections, don't bother.
Frequently Asked Questions
Does conversion reduce transcription quality?
Not in a noticeable way — conversion preserves the speech quality needed for the engines. What really affects accuracy is the quality of the original recording.
How much time does conversion add?
In general, seconds — proportional to file size. It's included in typical processing times.
My format isn't on any list. Will it work?
Send it and let validation decide — if there's a readable audio track, probably yes. If it's rejected, convert it locally to MP3/WAV and upload again.
Do I get the converted file back?
No — conversion is internal, only for transcription. If you share the transcription with audio in a format the browser can't play, an MP3 version is generated for the public player automatically.
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