Convert M4A to mono

Upload an M4A file and mix it down to a single mono channel.

Mono for the voice memo pipeline

Phone recordings are commonly stereo by default even though speech needs one channel. This tool downmixes your M4A to mono and re-encodes it as AAC, producing smaller files that transcription and voice APIs prefer.

Frequently asked questions

Do transcription services really prefer mono?

Most are built for it, and some charge per channel. Mono input avoids surprises in both quality and billing.

Will the memo sound different?

For speech, no. The two channels of a phone recording carry nearly identical content; the blend is indistinguishable in normal listening.

Is processing private?

Yes, recordings never leave your device.