Podcast File Formats Explained: MP3, AAC, and WAV for Podcasters

The format question has a one-sentence answer: export as MP3 at 128kbps stereo (or 64kbps mono for voice-only content). Every other decision in this guide is secondary to that. But knowing why that answer is correct — and understanding what each format actually does to your audio — is what prevents the specific mistakes that add distortion, bloat file sizes unnecessarily, or break compatibility on certain platforms.

MP3: The Universal Standard

MP3 (MPEG-1 Audio Layer III) has been the dominant audio format for internet distribution since the late 1990s. Its dominance is not because it is technically the best format – it is because it is supported everywhere, by every device, every operating system, every podcast app, every platform, and every web browser. For podcast distribution, compatibility matters enormously, and MP3 is the universally safe choice.

MP3 is a lossy compression format, meaning some audio data is permanently discarded during encoding to reduce file size. For voice content, this is not a meaningful quality issue at adequate bitrates. The human voice recorded cleanly at 128 – 192kbps MP3 is indistinguishable in quality from the uncompressed source for practical listening purposes.

When to use MP3: For all final podcast episode files published to your host and distributed to platforms. MP3 at 128 – 192kbps is the recommended format for podcast distribution.

AAC: Better Quality at Lower Bitrates

AAC (Advanced Audio Coding) is a more modern lossy compression format that produces better audio quality than MP3 at the same bitrate. An AAC file encoded at 128kbps sounds noticeably better than an MP3 at 128kbps. Apple developed AAC as part of the MPEG-4 standard, and it is the native audio format for Apple devices, iTunes, and Apple Podcasts.

Platform support for AAC: Apple Podcasts, Spotify, Amazon Music, and most modern podcast apps support AAC natively. However, some older podcast apps, third-party RSS readers, and certain embedded podcast players do not handle AAC as reliably as MP3. For maximum compatibility, particularly if your audience uses a range of listening apps and devices, MP3 is still the safer choice.

When AAC makes sense: If your entire distribution chain – hosting platform, apps your audience uses – supports AAC reliably, and file size efficiency is important (useful for mobile data consumption), AAC at 128kbps gives you slightly better quality than MP3 at the same size. In practice, for most independent podcasters, the difference is small enough that MP3 remains the simpler, more universal choice.

WAV: The Production Archive Format

WAV (Waveform Audio File Format) is an uncompressed audio format. WAV files contain the full, lossless audio data without any compression encoding. They represent the highest quality recording format and should be used as your working format throughout production and as your archival master.

The trade-off is file size. A one-hour stereo WAV file at 44.1kHz/16-bit is approximately 600MB. At 44.1kHz/24-bit (common for production work), it is roughly 900MB. This makes WAV impractical for podcast hosting and streaming – podcast hosts charge for storage and bandwidth, and large files increase listener buffering times.

When to use WAV: During recording and editing as your source files. As your final archived master before encoding to MP3 for distribution. WAV files allow you to re-encode at different bitrates or formats in the future without generation loss from double-compression.

Never use WAV for: Publishing to your podcast host, sharing episode files, or streaming distribution.

OGG Vorbis: Avoid for Podcasting

OGG Vorbis is a free, open-source audio format that produces good quality at low bitrates. Despite its technical merits, it is not widely supported by major podcast platforms or podcast apps. Apple Podcasts does not natively support OGG, and most podcast hosting platforms do not accept it as an upload format. There is no reason to use OGG for podcast distribution – use MP3 instead.

FLAC: Archive Quality, Not for Distribution

FLAC (Free Lossless Audio Codec) is a lossless compression format that reduces file size compared to WAV while retaining all audio data exactly. FLAC files are significantly smaller than WAV files (typically 40 – 60% the size) while being bit-for-bit identical in audio quality. Like WAV, FLAC is appropriate for archival storage but not for podcast distribution – it is not widely supported by podcast platforms or apps.

Recommended Workflow for Podcast Audio

1. Record to WAV or lossless format at 44.1kHz, 16 or 24-bit.
2. Edit in your DAW (Audacity, GarageBand, Adobe Audition) using your WAV files as source.
3. Export final mix to WAV – keep this as your archival master.
4. Encode for distribution: Export or convert your WAV master to MP3 at 128 – 192kbps, 44.1kHz.
5. Upload your MP3 to your podcast host.

What About Bitrate? A Practical Summary

• 64kbps mono: Usable for voice-only content in constrained bandwidth situations but noticeable compression artifacts. Not recommended for most podcast publishing.
• 128kbps mono: Recommended for solo voice shows. Excellent quality-to-size ratio. Half the file size of 128kbps stereo.
• 128kbps stereo: Minimum for shows with music, multiple voices, or production elements.
• 192kbps stereo: Standard for most produced podcast content. Good balance of quality and file size.
• 320kbps: Maximum MP3 bitrate. Imperceptible difference from 192kbps for voice content. Larger files with no practical benefit for podcasts.

Key Takeaways

• MP3 is the universally safe choice for podcast distribution, recommended at bitrates of 128 – 192kbps for optimal quality
• AAC offers better audio quality than MP3 at the same bitrate, with 128kbps AAC sounding better than 128kbps MP3
• WAV is an uncompressed format ideal for production and archival purposes, with a one-hour stereo file at 44.1kHz/16-bit being approximately 600MB
• While AAC is supported by platforms like Apple Podcasts and Spotify, MP3 remains the more compatible option across all devices and apps
• For most independent podcasters, MP3’s simplicity and universal support make it the preferred format despite AAC’s slight quality advantage at lower bitrates

Related Guides

• podcast audio quality standards
• submitting to Spotify
• submitting to Apple Podcasts
• CoHarmonify Podcast Studio