best free-of-charge spotify song recording software

There are several free software options that you can use to record or capture audio from Spotify. However, please note that recording music from Spotify goes against their terms of service, so proceed with caution and ensure you have the rights to the content you're working with. Here are some popular free options for audio recording software:

**Audacity**: A widely-used, open-source audio recording and editing software. Audacity lets you record audio directly from your computer's sound card.

**OBS Studio**: Originally designed for video streaming, OBS Studio can also capture audio. You can set it up to record the desktop audio, which includes sounds from Spotify.

**GarageBand** (Mac): If you are a Mac user, GarageBand is a free digital audio workstation that allows you to create and record music. 

**WavePad**: A free audio editing software that allows you to record audio from various sources, including from your computer.

**Soundtrap**: An online digital audio workstation that allows collaborative music creation and has a free tier that may suit your basic recording needs.

**Zencastr**: Primarily used for podcasting, Zencastr allows you to record audio directly from your browser, which includes the capability to capture sound from your system.

Always check the legalities of recording and using content, as different platforms have different policies.