Spotify didn't come with a feature to help you export playlist officially. Thankfully, you can backup Spotify playlists, songs to text files with web apps such as this app.

This app is the easiest way to backup all Spotify songs with one click. If you'd like to save your time, you can give it a try.

1. Launch app.
2. Log in with Spotify account and password and click "OK" to grant the access.
3. It takes a few minutes to scan your account depending on how many playlists you have.
4. When the scan completes, you can click "Export" to backup all Spotify playlists to JSON text file.