Which channel is L vs. R?

L = Left (channel 0), R = Right (channel 1). If an interview was recorded with Speaker A on the L mic and Speaker B on the R mic, you'll get A in the left file and B in the right file.

We append `-left.wav` / `-right.wav` (or `.mp3`) to the original filename. Example: `interview.wav` → `interview-left.wav` + `interview-right.wav`.

What about mono input?

We skip the split and write a single file (format conversion still runs). Handy for unifying MP3s as WAVs.

Does it support 5.1 / 7.1 multichannel?

No — this tool covers stereo → two mono files and mono passthrough only. For surround, use a DAW (Reaper / Logic) or ffmpeg's `-filter_complex channelsplit`.

Is anything uploaded?

No. Decoding runs via the Web Audio API and MP3 encoding uses a JS port of LAME (lamejs) — all local.

Back to Audio

Audio channel split — stereo to two mono files

Split a stereo audio file (MP3 / WAV / M4A / FLAC / OGG) into separate left and right mono WAV / MP3 files. Useful for interview / dictation / Zoom recordings captured with one speaker per channel, isolating noise on one side, or pulling a single channel into your DAW. Mono input passes through as a single file. Everything stays in your browser.

audio

How to use

Drop or pick one or more stereo audio files (MP3 / WAV / M4A, etc.). Choose the output format (WAV / MP3). For MP3 you can pick a bitrate. Click Split channels to write the left and right channels as separate mono files. Save each file individually or grab everything as a ZIP. Mono input passes through as a single file (format conversion still runs).

FAQ

Which channel is L vs. R?: L = Left (channel 0), R = Right (channel 1). If an interview was recorded with Speaker A on the L mic and Speaker B on the R mic, you'll get A in the left file and B in the right file.
How are files named?: We append `-left.wav` / `-right.wav` (or `.mp3`) to the original filename. Example: `interview.wav` → `interview-left.wav` + `interview-right.wav`.
What about mono input?: We skip the split and write a single file (format conversion still runs). Handy for unifying MP3s as WAVs.
Does it support 5.1 / 7.1 multichannel?: No — this tool covers stereo → two mono files and mono passthrough only. For surround, use a DAW (Reaper / Logic) or ffmpeg's `-filter_complex channelsplit`.
Is anything uploaded?: No. Decoding runs via the Web Audio API and MP3 encoding uses a JS port of LAME (lamejs) — all local.

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