Convert PART to MP3

Can I somehow convert .part files to .mp3 format?

How to convert part to mp3 file

It is unfortunately not possible to directly convert Partially Downloaded Files to MP3 Audio Files (.part to .mp3 conversion).

Try renaming the file's suffix from PART to MP3. The file might be playable via some modern media player. In most cases, however, such files will be corrupted.

Your only option is to download the file again. In best-case scenario, the system will allow you to resume downloading the already partially downloaded PART file.

Simply put, it is impossible to convert PART to MP3 directly.
Thus, there is no so-called part to mp3 converter or a free online part to mp3 converter to be found.