Average Age of Mass Shooters in the U.S. (Updated 2026)

Last Updated: Mar 6, 2026

28-year-olds committed the most mass shootings between 1966 and 2025.
The youngest mass shooter in U.S. history was 11.
The oldest mass shooter in U.S. history was 72.
Five of the ten deadliest mass shootings in the U.S. were committed by individuals in their 20s.

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Methodology

Mass shootings, as defined in this article, are those in which four individuals are killed with a firearm (not including the shooter). These shootings occur in public places and do not involve familial disputes, drugs, or other crimes.

We cross-referenced multiple sources and investigated news articles to ensure accurate reporting.

Average Age of Mass Shooters

Between 1966 and 2025, there have been 202 mass shootings. Of those, the average shooter was 34 years old.^{(1, 2, 3, 4)}

Infographic Breaking Down the Age of the Shooter and Number of Victims

Age Range and Distribution

Relative to other age groups, individuals in their 20s committed a disproportionate number of mass shootings (70 incidents) between 1966 and 2025. Among them, 28-year-olds committed more mass shootings than individuals of any other age (10), followed by 21- and 25-year-olds (9).

Those in their 40s committed 49 mass shootings, while those in their 30s committed 40. Teenagers and individuals over 50 were least likely to commit mass shootings.^{(1, 4)}

Breakdown of Mass Shooting Total Occurrences Based on Age

Youngest Mass Shooters

The youngest mass shooter in U.S. history was Andrew Golden (age 11). His accomplice, Mitchell Johnson, was the second youngest (age 13). The duo killed four students and one teacher, and injured ten other children.^{(1, 3, 4)}

Oldest Mass Shooters

The oldest mass shooter in U.S. history was 72. Six mass shooters were in their 60s, and 15 were in their 50s.^{(1, 3)}

Is There a Link Between Shooter Age and Number of Victims?

There is a strong concentration of mass shooters in their 20s, 30s, and 40s, which also equates to more victims. Teens averaged 16.1 victims per shooting. Attackers in their 20s had averaged 17.4 victims per shooting, those in their 30s averaged 11.4 victims per shooting, and those in their 40s averaged 10.8 victims per shooting.

Attackers in their 60s averaged the most victims per shooting (162.8) due to the 2017 Las Vegas Route 91 shooting. That shooting claimed 60 lives and resulted in a total of 927 victims.

Over three-fourths (78%) of mass shooters in the U.S. were between the ages of 20 and 49 between 1968 and 2025.^{(1, 4)} Teens and individuals over 50 years of age were less likely to commit mass shootings than all other age groups.

Attackers were most likely to commit a mass shooting in their 20s (70). Those in their 40s were second most likely to commit mass shootings (49), while those in their 30s were only slightly less likely to commit a shooting (40).

Mass Shootings and Age: Wrap-Up

Mass shooters in the U.S. range in age from 11 to 72. Twenty-year-olds committed more mass shootings and injured more people than any other age group from 1966 to 2024.

Twenty-eight-year-olds committed more mass shootings than any other age group, but the deadliest mass shooting in history was committed by a 64-year-old man. Therefore, there is no apparent direct link between the number of victims and the perpetrator's age.

Sources

Written by

Cassandra McBride