Podcast Audio Converter
iPhone Voice Memos and Zoom’s audio-only recordings are M4A files. Audacity, and most audio interfaces produce WAV. Your podcast host wants MP3, and your editor may want WAV. This converter turns MP3, WAV, M4A, FLAC, AAC, OGG, Opus, and AIFF files into MP3 and WAV, in mono or stereo.
Common podcast conversions
- M4A to MP3. Make voice memos, Zoom audio, and GarageBand exports playable by any host or editor.
- WAV to MP3. A 60-minute stereo WAV is about 635 MB. As a 128 kbps MP3 it can be compressed to about 10% of that.
- MP3 or M4A to WAV. For editors and engineers who ask for uncompressed audio. (WAV can’t restore detail the MP3 or M4A already lost, but might better work in some programs).
- FLAC to MP3. Compress large FLAC files to smaller MP3.
- Compress an MP3. Re-encode a large MP3 file at a lower bitrate to shrink downloads for listeners on mobile data.
Which bitrate should a podcast use?
- 64 to 96 kbps, mono. Solo shows and interviews. Apple recommends 64 to 128 kbps for mono.
- 128 kbps. Speech with music. The usual default.
- 192 kbps, stereo. Music-led or sound-designed shows. Apple recommends 128 to 256 kbps for stereo.
Above 192 kbps, voices don’t sound better, and files get bigger.
Mono or stereo?
Choose mono for voice. It halves the file size at the same bitrate. It also fixes recordings where the host is on the left channel and the guest on the right, which headphone listeners hear in one ear each. Keep stereo for music and stereo sound design.
Apple Podcasts Connect does not accept single-channel WAV or FLAC, so choose stereo for WAV files you upload there. Spotify accepts mono and stereo.
Frequently asked questions
What is the best audio format for a podcast?
MP3 plays everywhere. Apple prefers AAC for feeds because it sounds slightly better at the same bitrate, but MP3 is accepted by every app and host. Keep a WAV master of each episode. This converter exports MP3 and WAV, not AAC.
Does converting MP3 to WAV improve quality?
No. It makes editing easier and prevents further loss, but it can’t bring back what the MP3 removed.
How do I convert an iPhone voice memo to MP3?
In Voice Memos, tap the recording, then Share, then Save to Files. Open the M4A here and convert it to MP3.
What sample rate do exports use?
44.1 kHz, which every podcast platform accepts. 48 kHz recordings are resampled.
Is there a file size limit?
Inputs and exports can each be up to 256 MB. Long stereo WAV exports reach that quickly, so use MP3 or mono for full episodes.
