Hello! It is difficult for the human ear to tell the difference between lossless music and mp3, because when the lossless format is converted to mp3 format, only the part beyond the hearing range of the human ear is removed, so if you are not a very professional equipment player, you will not be able to hear it. If you want to identify it, you can use software such as Foobar or Cool Edit to analyze the music. You can identify it by observing the spectrogram. If it is a music file in a pseudo-lossless format, the spectrum above 16kHz is basically cut off. However, there are also a few boring people who convert files with compromised sound quality into lossless formats, which are almost indistinguishable. However, this is rare, so you can generally rest assured.