Compress M4A files

Upload an M4A file and shrink its size.

Quality

Smaller M4A files on demand

The tool re-encodes the AAC audio in your M4A at a lower bitrate. AAC degrades gracefully, so voice recordings in particular can drop a long way in size before sounding rough.

Where smaller M4As matter

Voice memos that exceed messaging app limits, lecture archives accumulating on a phone, audiobook files for storage-starved devices, and recordings attached to tickets, forms, or emails with hard caps.

Frequently asked questions

How far can I compress a voice memo?

A long way. Speech at modest AAC bitrates remains fully intelligible; an hour of voice can land in the tens of megabytes.

Does compressing M4A lose quality?

Yes, some, since this is a lossy re-encode. Pick a higher setting for music and a lower one for speech.

Is my recording uploaded?

No, compression is performed locally by your browser.