Convert stereo to mono
Fold two channels into one, halving the size of a recording that never needed both.
Drop a file to start
Runs in your browser. Nothing is uploaded.
Most spoken-word recordings are stereo by accident. One microphone, two identical channels, twice the file size for no information at all — or worse, a recording where the speaker ended up almost entirely in the left channel and anyone listening on one earbud hears nothing.
Folding to mono fixes both. The channels are mixed the way the Web Audio specification says they should be, which is the same arithmetic every browser and editor uses, so nothing cancels out or jumps in volume unexpectedly.
The file gets meaningfully smaller — close to half for uncompressed formats, less but still substantial for compressed ones, since the encoder no longer has a second channel to describe. For podcasts, lectures, interviews and voice notes there is no reason not to, and plenty of speech tooling expects mono anyway.
Step by step
- 1Drop in the files.
- 2Choose the output format.
- 3Press Convert, then download.
Questions
Will it sound different?
On a single-microphone recording, no. On genuinely stereo music you lose the width, and anything relying on the difference between the channels goes away.
How much smaller is the file?
About half for WAV and FLAC. For MP3 or Opus it is less than half, but still a large saving.
Is one channel discarded?
No, they are mixed together. Discarding one would lose whatever was only in it.