How to use the channel splitter
- Add a stereo or multichannel file. MP3, M4A, WAV, OGG, FLAC, WebM, and the audio of MP4, MOV or MKV video are accepted.
- Choose Save each channel as: WAV 16-bit or WAV 24-bit.
- Press Split channels.
- Download each file. A stereo input gives
name-left.wavandname-right.wav. The Channel levels table lists the Peak and RMS of each one.
A mono file returns “This file is mono — there is only one channel to split.”
What it does and when to use it
Splitting is useful when the two channels hold different things:
- Two-microphone interviews and podcasts recorded with one person per channel, so each voice can be cleaned and levelled on its own.
- Camera audio where a lapel mic is on one channel and the camera’s own microphone on the other. Keep the better one.
- Test and measurement, for example a reference signal on the left and the device’s output on the right.
- Checking a recording where one side sounds wrong. The level table quickly shows a dead or much quieter channel.
Once split, bring a file back to two channels with mono to stereo, level each one with the audio normaliser, or join them end to end with the audio merger.
How it works
The file is decoded in a Web Worker on your device into one list of samples per channel. Each list is copied unchanged into its own one-channel WAV at the source’s sample rate, as 16-bit or 24-bit PCM. Nothing is mixed, filtered or resampled. For the table, the tool finds each channel’s highest sample (Peak) and its root-mean-square level (RMS), both in dBFS, where 0 dBFS is full scale.
Worked example
A 10-second stereo test file, with a louder tone on the left and a quiet one on the right, produced:
| Channel | Peak | RMS |
|---|---|---|
| left | −6 dBFS | −9 dBFS |
| right | −20 dBFS | −23 dBFS |
The summary read “2 mono files · 0:10.00 each”, and each 16-bit file was 861.4 KB. The 14 dB gap between the channels is the kind of difference worth checking before you mix them.
Limits and tips
- If both files sound identical, the source was mono saved as stereo and splitting gains nothing.
- Output is always WAV; convert afterwards if you need a compressed file.
- This tool has no ffmpeg option, so AIFF, AMR, WMA and CAF files cannot be opened here. Convert them first with audio to WAV, which can use the fallback.
- Other formats depend on WebCodecs in your browser (current Chrome, Edge, Firefox, or Safari 26+). Long multichannel recordings use a lot of memory on phones.
Frequently asked questions
Can this separate the vocals from the music?
My interview has one person on each channel. Will this separate them?
What happens with a 5.1 or 4-channel file?
Why is my right file silent?
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