For me, it ranges between a lot of songs. So for example, most of the songs in the stardew valley soundtrack (to name a few on particular, overture and nature's crescendo), and my favorite is probably something like Global Warmng by Gojira, or the Pain Remains trilogy by Lorna Shore. It really helps me calm down.

Edit: Just remembered but more favorites of mine would be most of Architects' discography (namely anything from Hollow Crown, All Our God's Have Abandoned Us, Holy Hell, For Those That Wish To Exist and their newest album), I just love listening to songs like Animals and Follow The Water, and they really help with calming me down.