Podcast Audio Quality: Spotify and Apple Podcasts Standards

A listener cannot tell you your episode is too loud or too quiet. They just stop listening. Platform normalization means an episode mastered at the wrong loudness level will sound off when played back-to-back with other shows — too jarring, too flat, or dynamically crushed. They move on. Meeting audio quality standards is not about satisfying a checkbox. It is about not being the show that sounds subtly wrong in ways the listener cannot name but absolutely notices.

The Number That Determines How Loud Your Episode Sounds on Every Platform

Loudness is measured in LUFS (Loudness Units relative to Full Scale), which is a perceptually-weighted measurement that correlates better with how loud something sounds to human ears than simple decibel peak levels.

Platform recommendations:

• Apple Podcasts recommends -16 LUFS for stereo files and -19 LUFS for mono files (integrated loudness). This is a recommendation, not a hard technical requirement – Apple does not reject episodes that differ, but episodes mastered to these values will sound appropriately balanced on their platform.
• Spotify normalizes all audio to approximately -14 LUFS on playback. This means if you master your episode louder than -14 LUFS, Spotify will turn it down to match. Mastering significantly above -14 LUFS does not make your podcast louder on Spotify – it just means Spotify applies more volume reduction and may affect dynamic range.

True peak – the maximum instantaneous level of your audio – should not exceed -1 dBTP (decibels True Peak). Levels above this can cause distortion when the file is decoded and played back, particularly after any encoding conversion.

Practical target for podcast mastering: aim for approximately -16 LUFS integrated loudness and a true peak of -1 dBTP or below. This works well across Apple Podcasts, Spotify, and other platforms.

File Format: MP3, AAC, and WAV

MP3 (MPEG-1 Audio Layer III) is the universally accepted format for podcast distribution. Every podcast platform, every podcast app, and every device supports MP3. It is the safe, compatible choice for all podcast publishing.

AAC (Advanced Audio Coding) is also accepted by most major platforms including Apple Podcasts and Spotify. AAC achieves better audio quality than MP3 at the same bitrate – meaning an AAC file at 128kbps sounds noticeably better than an MP3 at 128kbps. However, AAC has slightly less universal compatibility than MP3, particularly with older podcast apps and devices. For maximum compatibility, use MP3.

WAV (Waveform Audio File Format) is an uncompressed audio format. WAV files are the highest quality and should be used as your working and archival format during production. However, WAV files are approximately ten times larger than equivalent MP3 files – a one-hour stereo WAV file at 44.1kHz/24-bit is roughly 900MB. This makes WAV impractical for podcast hosting and streaming. Do not publish WAV files to your podcast host.

Bitrate Recommendations

Bitrate determines the amount of data per second in your compressed audio file. For spoken word podcast content:

• 128kbps: The minimum acceptable quality for podcast publishing. Sufficient for clear voice audio, though some compression artifacts become noticeable at lower frequencies.
• 192kbps: The recommended standard for podcast publishing. Good quality-to-file-size balance for voice content. Suitable for virtually all podcast formats including music-heavy shows.
• 320kbps: Maximum MP3 bitrate. Produces larger files than 192kbps with negligible perceptual improvement for voice-only content. Not necessary for podcasts.

For a solo voice show, 128kbps mono is perfectly adequate and produces small file sizes. For shows with music beds, multiple voices, or high production value, 192kbps stereo is a reasonable standard.

Sample Rate

44.1kHz is the standard sample rate for podcast audio. 48kHz is also widely supported and is the standard for video production. Either is acceptable; 44.1kHz is slightly more standard for audio-only content. Avoid non-standard sample rates like 22.05kHz – they can cause compatibility issues with some players and processing tools.

Mono vs. Stereo

For solo voice podcast content, mono is entirely appropriate and cuts your file size roughly in half compared to stereo. Listeners on earbuds or headphones hear mono content clearly in both ears, and podcast apps handle mono files correctly. There is no quality penalty for publishing mono voice content.

Interview shows recorded with multiple microphones are often published in stereo, and in some cases producers hard-pan each voice to a different channel. This practice is less common now than it was historically – most current production standards keep voices in the center for earphone listeners.

Loudness Normalization in Production

Free tools to measure and adjust loudness:

• Auphonic – cloud-based audio post-production tool that applies loudness normalization, noise reduction, and leveling automatically. Has a free tier with a monthly usage limit.
• Audacity – free, open-source audio editor with a loudness normalization effect built in.
• Adobe Podcast Enhance – free AI-powered tool for improving voice recording quality and noise removal.

Platforms like CoHarmonify apply loudness normalization as part of their audio generation and mastering process, producing output that meets standard platform specifications without requiring manual post-processing.

Key Takeaways

• Apple Podcasts recommends mastering episodes to -16 LUFS for stereo and -19 LUFS for mono files
• Spotify normalizes audio to approximately -14 LUFS, meaning louder episodes will be turned down
• True peak levels should not exceed -1 dBTP to avoid distortion during playback
• MP3 is the universally accepted format for podcast distribution, while AAC offers better quality at the same bitrate
• For spoken word content, a bitrate of 128kbps is the minimum acceptable quality for podcast publishing

Related Guides

• choosing the right microphone
• podcast file formats explained
• recording without a studio
• Spotify submission requirements
• Apple Podcasts submission requirements
• CoHarmonify Podcast Studio