How old was MJ in the bad era?

Between 28 and 31 years old. Maybe 32 years old too..
Some are saying 1986-1989, some 1986-1990.

MJ began working with the demos for the Bad album in 1985, and recorded and released it in 1987, two days after his 29th birthday. The Bad tour started in Sept. 1987, and ended in Jan. 1989. His siguiente album Dangerous was released when Michael was 33, in Nov. 1991.

28

He was in this thirties

29 years old

He was about 28 o 29

I think probably his early - mid 20s... it seems like that

I think that he was 28 o 29. Not really sure

28-:31 the bad era