Everything you need to know about M4P files and transcription

M4P files represent a specific era in digital audio history. When Apple launched the iTunes Store in 2003, all purchased music was sold in M4P format with FairPlay DRM encryption. This meant that music files purchased through iTunes could only be played on authorized Apple devices and through the iTunes application. The DRM protection prevented users from freely copying, sharing, or processing these files with third-party software.

In 2009, Apple announced that all music on the iTunes Store would be sold DRM-free in M4A format (branded as "iTunes Plus"). This was a major shift that made purchased music more portable and compatible with a wider range of devices and software. However, millions of M4P files from the pre-2009 era still exist on people's computers and in their iTunes libraries. If you have M4P files that contain spoken content, interviews, recordings, audiobooks, or podcasts from that era, you may want to transcribe them.

The DRM challenge for transcription

The fundamental challenge with M4P files is that the DRM encryption prevents most software from reading the audio data. Transcription tools, including Speak AI, need access to the raw audio stream to perform speech recognition. DRM blocks this access. This is why the conversion step (M4P to M4A or MP3) is necessary before transcription can happen.

The good news is that for music purchased through iTunes, Apple's own tools make this conversion straightforward. If you have an Apple Music subscription ($10.99/month) or iTunes Match ($24.99/year), you can re-download your purchased tracks as DRM-free M4A files. This is the cleanest and most reliable method. For files that cannot be re-downloaded, third-party conversion tools offer an alternative.

Beyond M4P: other audio formats Speak AI supports

Once you have converted your M4P file to a standard format, Speak AI's audio-to-text converter handles the rest. The platform supports a comprehensive range of audio formats including MP3, M4A, WAV, OGG, FLAC, AAC, WMA, WebM, and more. Video formats like MP4, MOV, AVI, and MKV are also supported, with audio automatically extracted for transcription. If you have other unusual formats, check our OGG-to-text conversion guide for another example of how the process works.

Use cases for transcribing M4P audio

While M4P is most commonly associated with music, there are legitimate use cases for transcribing M4P audio content. Audiobooks purchased through the old iTunes Store may be in M4P format. Spoken word content, lectures, and educational audio sold through iTunes may also use M4P. Podcast episodes downloaded through early versions of iTunes could be in protected format. In each case, converting to a standard format and transcribing with Speak AI gives you a searchable, analyzable text version of the content.