Spotify offers automatic, low, normal, high, and very high quality with different bitrates for different users by formatting the music as OGG Vorbis format. Following is the full table about all the bitrates that Spotify streaming at.
|Bitrates||Streaming Quality||Free or Premium||Platforms|
|24 kbps||Low||Both||Desktop, mobile and tablet|
|96 kbps||Normal||Both||Desktop, mobile and tablet|
|128 kbps||Normal||Free||Web Player (AAC)|
|160 kbps||High||Both||Desktop, mobile and tablet|
|256 kbps||High||Premium||Web Player (AAC)|
|320 kbps||Very High||Premium||Desktop, mobile and tablet|
Don't know what bitrate does Spotify stream at? Here is the detailed post about Spotify bitrate and an extra way to download Spotify Music with high quality.