Audio Channel Converter

Stereo to mono, or mono to stereo, in one click. Pick the downmix source (L+R sum, L only, R only) and toggle auto-normalize to avoid clipping.

What it does

Drop an audio file. Pick a direction (stereo→mono or mono→stereo). For downmix, pick the source: sum both channels, take just the left, or take just the right. Auto-normalize scales the output so the loudest sample sits at exactly 0 dBFS — no clipping, no quiet output.

Mono→stereo simply duplicates the single channel into both. There's no spatialisation pass; output is centered.

How to use it

  1. Drop the file — Any common audio format.
  2. Pick direction and source — For voice/podcast content, downmix to mono saves space. For a music track that uses one channel for vocals, pick that channel only.
  3. Process — Auto-normalize is on by default. Turn it off if you want absolute output levels preserved.

When to use it

Podcast prep

Convert stereo recordings to mono — saves half the file size with no audible loss for spoken content.

Voice memo cleanup

Bad mic placement on one channel? Pick the other channel directly.

Mono source needs stereo output

Some publishing platforms require stereo files. Convert mono→stereo before uploading.

FAQ

Why does the L+R sum clip?
If both channels have a peak at the same instant, the sum can hit 2.0 — well past 0 dBFS. Auto-normalize divides by the max to keep the result within range.
Will mono→stereo make it sound 'stereo'?
No. It just sends the same signal to both speakers. True stereo separation requires multi-track sources.