The larger mp3 files are mainly due to the high bit rate (such as 320Kbps). You can use Baidu Music’s own format conversion tool to convert files with a higher bit rate into files with a lower bit rate, thus To change the file size, click "Format Conversion" under "Gadgets" on the right side of Baidu Music Player;

Baidu Music

Methods/Steps

Click on the upper left Add files in the corner, find the music to be compressed, and add it to Baidu Music

On the interface you can see the constant bit rate, variable length bit rate, and average bit rate.

We choose the average bit rate here. You can see that the default is 320kbps. Pull down to find 32kbps, select the place to convert to, and start conversion

Baidu Music is just a tool. For example, Kugou, Kuwo, etc. all have small tools for converting this format.