Serial Killer Statistics

Written by Taylor Stacy:


Americans seem to have a strange fascination with serial killers. For decades, we as a nation have been enthralled by the idea of someone who kills for pleasure. In 1979, the trial of Ted Bundy was among the first to be televised nationally and was watched by millions of Americans. In the twenty-first century, documentaries chronicling the murders of America’s most prolific killers are some of the most watched shows on streaming services. The most recent example is “Dahmer – Monster: The Jeffrey Dahmer Story,” the dramatic retelling of the life of Milwaukee serial killer Jeffrey Dahmer. Netflix reported that the show is their second most-watched series of all time. There are many theories surrounding why we are fascinated by serial killers. There’s also extensive research about serial killers themselves, their methods of killing, and why they wound up killers to begin with. Researchers seem to be equally interested in both kinds of data, but this article will focus on the latter kind.

Searching for Stats

Radford University and Florida Gulf Coast University have a jointly operated database that keeps track of serial killers, their years of operation, their victims, and their methods of execution. Each year, the team behind the database releases an annual report on serial killer data. They somewhat playfully refer to this data as Serial Killer Statistics.

The database tracks serial killings all the way back to 1900 and includes serial killers from over 115 countries. The U.S. leads the rest of the world in documented serial killers, with a whopping 3,613 serial killers as of 2020 (England is not-so-close second, with known 176 serial killers as of 2020). The data tracks the number of serial killers that have been active each year too, with 1986 being the peak in the U.S. Generally, murders by serial killers in the U.S. was at its highest between 1970 and 1990, which is when some of the most sensationalized killers were active (think Bundy, Dahmer, Ramirez, Gacy, and Kemper, among many more). That number, though, has steadily declined in recent years, although the wealth of content about them could fool you.

Gender(ed) Differences

To anyone who has ever studied crime (or even just listened to every episode of a true crime podcast), it is no surprise that most serial killers are male. A leading theory for this phenomenon is that men are simply more violent than women. In the world, men are arrested at almost four times the rate as women for violent crimes. Another theory regarding why there are more male serial killers rests on the recurring finding in clinical psychology that men are more likely to have paraphilias (atypical “turn-ons”) than women.  This theory is especially pertinent in cases where sexual desire appears to have been a prime motive. Only 8.6% of known U.S. serial killers are female. In terms of motive, composited data shows that almost 70% of female serial killers acted for financial gain. In contrast, only 28.8% of male serial killers were motivated by financial gain. This is still the largest single motive for all serial killing, but close behind is killing for sexual pleasure, which comes in at 27.3%. For both male and female serial killers, involvement in organized crime (including gangs, mobs, etc.) was the lowest recorded reason for serial killing, comprising 6.2% of known male serial killers and 0.5% of known female serial killers.


Despite the current interest in studying serial killers, serial killings have drastically decreased in the last couple of decades. As the face of sensationalized crime continues to change, the serial killers of the twentieth century continue to capture the attention of millions. Social scientists continue to be right behind it all, collecting data and trying to figure out why these crimes occur–and why we love to watch.