Is WAV more accurate than MP3?

Marginally, and only on already-difficult audio. Compression removes what the ear can't hear, and speech recognition doesn't use that either.

Should I compress it before uploading?

No need. Up to 10 GB goes up as it is, and converting first costs you time and adds a step where things break.

My WAV is over 10 GB. Now what?

That's around fifteen hours of stereo. Split it by session, or convert that one to MP3 — at that length the quality difference is irrelevant.

Does 24-bit or 96 kHz work?

Yes. Higher rates don't improve transcription, but they don't break it either.

Does a WAV transcribe better?

Practically the same as a normal-quality MP3. The difference between the two formats lives in frequencies a voice doesn't use, so it doesn't change what can be understood.

How long does an hour-long WAV take to upload?

It depends on your connection: around 600 MB on a normal home upload is several minutes. If you're in a hurry, convert it to MP3 first and it drops to about 30 MB.

Try it without an account

Transcribe a WAV file

Uncompressed audio, transcribed exactly as recorded. Big files welcome: up to 10 GB, straight from the recorder.

Drag your file here

MP3, WAV, M4A, MP4, MOV… up to 10 GB

Up to 10 GB, so an hour of 48 kHz fits with room to spare
No conversion and no quality loss before transcribing
Any sample rate and bit depth your recorder writes

WAV

What this tool does

WAV is what a decent recorder writes when you tell it not to compromise: no compression, nothing thrown away, the waveform as the microphone heard it. It's the best possible input for speech recognition, and also the heaviest.

An hour of stereo WAV at 48 kHz is around 600 MB — roughly sixty times an MP3 of the same hour. That's the only real friction here, and it's an upload problem, not a transcription one: you can drop files up to 10 GB and there's no need to compress them first.

What we handle that others don't

Any sample rate and bit depth: 44.1 or 48 kHz, 16 or 24 bit, mono or stereo.
Files up to 10 GB, which is several hours of uncompressed audio.
No re-encoding: what gets transcribed is what your recorder wrote.
Multi-microphone recordings separate into speakers properly.

How it works

1
Drop the WAV
It uploads straight from your browser to storage, without passing through anything else.
2
We transcribe it
Same speed as any other format: what counts is the length, not the weight.
3
Take the text
With timestamps, speakers and the summary if you asked for one.

What people use it for

Field recordings

Handheld recorders write WAV by default, and that's the file to use.

Studio sessions

The raw track transcribes as well as the mastered one — often better.

In detail

Why a WAV weighs so much

Because it compresses nothing. It stores every sample of the sound exactly as it came in: 44,100 samples a second, two channels, two bytes each. That's ten megabytes a minute, six hundred an hour, and a full day of recording can approach five gigabytes.

In exchange it's the format that loses nothing, which is precisely what you want when the recording is a master to be archived or material heading into an editor. For transcription it isn't necessary — the result is identical to a decent MP3 — but it does no harm either.

Uploading a gigabyte without drama

The per-file limit is 10 GB, and the upload goes straight from your browser to storage without a middleman slowing it down. Even so, on a home connection, a gigabyte takes several minutes, so there are two shortcuts.

The first is trimming what you don't need before uploading. The second is converting the WAV to 96 kbps MP3: the file drops to about 5% of its size, the transcript comes out exactly the same, and the upload stops being a problem. Both can be done right here, free, without uploading anything.

Questions

And if what you have is the video?

Upload it and you'll get the transcript with timestamps, the speakers separated by name and a summary with the key points. You can start without an account.

Transcribe my recording See prices

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