Audacity is a free, cross-platform audio editing software. You can use it to, for instance, cut an MP3 file regardless of the operating system you use. Whether Linux, macOS or Windows. Audacity is capable of handling MP3 files, but it needs an additional encoder to be able to convert them back to MP3 format after you have edited them. The encoder is Lame.
When you are opening an MP3 file in Audacity, the software will turn the MP3 format into an editable format to allow you edit the file. Once the editing process is done, you need to convert the editable format back to MP3 format to make it playable on regular MP3 players. If you use Audacity on Linux, chances are you don’t need to install the Lame encoder anymore. In most cases, Lame is already installed upon the installation of Audacity.
In Windows, you need to install the Lame encoder separately.
Installing Lame encoder on Windows
Assuming you have installed Audacity on your Windows, you can visit this page to download the Lame encoder for Windows. There are lots of links here. You can download the recommended installer package.
Simply double-click the installer package (the EXE file) to install it. Once the encoder is installed, you will be able to covert an audio file you are editing with Audacity to MP3.
How to cut an audio file with Audacity
To edit an audio file in Audacity, you need to open the file first. You can open the file you want to edit by clicking the File menu and select Open (Ctrl+O).
Use the Selection Tool (F1) to select the part you want to cut/remove and the Cut Tool (Ctrl+X) to cut it. Take a look at the screencast below.
To convert the audio file you have edited to MP3 format, click the File menu and select Export -> Export as MP3.
Select the destination where you want the converted file to be saved to and click the Save button. Before clicking this button, there are some options you can select. Like Bit Rate Mode, Quality, Variable Speed and Channel Mode.
On the next step, you can also edit the metadata tags of the song if you want. You can add tags like artist, track title, album and so on.