You can use
This is a special form of the
:N,Mbdelete ranged buffer delete command
% indicates all buffers rather than a numbered range.
I find this useful to clear down all buffers after a single logical change is complete. This is commonly when I’ve reached a point where I can commit.
It’s similar to dropping all your open browser tabs. It’s helpful to start working on the next logical change with a clean slate of buffers.