Definitely not. Dexter is a work of fiction. The storyline and everything about it are products of the imagination of the creators. There's no truth to it in the real world.
Dexter is not based on a true story. It's a work of imagination that combines elements of crime, drama, and psychology to create an engaging fictional narrative.
The fact that Dexter tries to cover his tracks and blend into society is based on true - life serial killers. In real cases, killers often go to great lengths to appear normal. Dexter's meticulousness in his killings and his attempts to not get caught mirror what real - life criminals do. Also, the idea of his 'dark passenger' can be related to the inner compulsions that real - life killers experience, although it is a more fictionalized representation.
Yes, 'Dexter' is based on a true story to some extent. The concept of a serial killer who uses his knowledge of forensics to cover his tracks while having his own moral code (however twisted) was inspired by real - life cases where criminals with unusual skills or occupations were involved in illegal activities.