How to use the M4A Compressor
- Choose the M4A.
- Pick a lower bitrate.
- Tick Mono for voice memos.
- Compress and download.
Voice memos
iPhone voice memos are recorded as M4A. Long recordings such as meetings and lectures can be compressed to 48–64 kbps mono with no loss of clarity for speech, cutting the size by more than half.
Good to know
Lossy files keep their format and are re-encoded at the bitrate you choose. Lossless or uncompressed files are saved as MP3 (or stay WAV on the WAV compressor). Tags such as title and artist are kept where the format supports them.
Supported files
MP3, WAV, M4A, AAC, OGG, OGA, FLAC, OPUS, WMA, AIFF, AIF, AIFC, ALAC, AMR, AC3, MP2, M4B, M4R, CAF, AU, WEBA, 3GA, APE and VOC. Files up to 1 GB each.
Frequently asked questions
Does the M4A still work in Apple apps?
Yes, it stays AAC in an M4A file.
How much does the M4A Compressor cost?
Nothing. It is free with no registration, no watermark and no limit on how many files you convert.
Is my file uploaded to a server?
No. The converter runs inside your browser using WebAssembly, so your file is processed on your own device and never sent to us or anyone else.
Does it work on iPhone and Android?
Yes, in Safari, Chrome and other modern mobile browsers. Short files work best on phones; for long or high-resolution videos a computer is faster.