As of June 19, 116 school shooting incidents were recorded in K-12 schools in the United States in 2025. Within the provided time period, the greatest number of K-12 school shootings was recorded in 2023, at 350. The source defines a school shooting as every time a gun is brandished, fired, or a bullet hits school property for any reason, regardless of the number of victims (including zero), time, day or the week, or reason, including gang shootings, domestic violence, shootings at sports games and after hours school events, suicides, fights that escalate into shootings, and accidents.

As of June 2022, there were 153 school shootings in total in the United States in that year. Of these incidents, only two were active shooter incidents. The largest number of active shooter incidents in schools was in 2018, with 11 active shooters.

The source defines a shooting as any time a gun is brandished, fired, or a bullet hits school property for any reason.

As of March 19, ***** school shootings were recorded in the United States in 2025, impacting K-12 school grounds and college campuses nationwide. In comparison, there were ** school shooting incidents recorded in 2024. In addition to schools, gun-related violence occurs in many public places within the United States, including workplaces, churches, restaurants, and nightclubs. The source defines school shootings as incidents of gun violence which occurred on school property and at least one person was shot, not including the shooter. School property includes, but is not limited to, buildings, fields, parking lots, stadiums and buses. Accidental discharges of firearms are included, as long as at least one person is shot, but not if the sole shooter is law enforcement or school security.

As of August 11, there were four mass shootings in the United States in 2025. This is compared to one mass shooting in 1982, one in 2000, and 12 mass shootings in 2022 and 2023. School shootings The United States sees the most school shootings in the world. Some motivations for school shootings included depression, seeking revenge, and bullying. As a result of the large amount of school shootings, gun control has become a central topic in U.S. politics. This widespread problem happens across the United States; however California saw the highest number of K-12 school shootings in the United States since 1970. However, the deadliest school shooting (as of October 2023) was the Virginia Tech massacre in 2007. This tragedy left 33 dead and 23 injured. Mass shooting issues Mass shootings happen when there are several injuries or deaths from a firearm-related violence. Throughout the last century, mass shootings have become an epidemic in the United States. However, despite the increase in mass shootings and number of casualties, the U.S. government has done little to prevent future shootings from happening. As a result of the lack of cooperation in politics, mass shootings have become an important issue for Generation Z living in the United States. Furthermore, having the right to bear arms is a popular belief in the U.S. and the percentage of households in the United States owning at least one firearm has remained somewhat steady since 1972.

THIS DATASET WAS LAST UPDATED AT 7:11 AM EASTERN ON DEC. 1

OVERVIEW

2019 had the most mass killings since at least the 1970s, according to the Associated Press/USA TODAY/Northeastern University Mass Killings Database.

In all, there were 45 mass killings, defined as when four or more people are killed excluding the perpetrator. Of those, 33 were mass shootings . This summer was especially violent, with three high-profile public mass shootings occurring in the span of just four weeks, leaving 38 killed and 66 injured.

A total of 229 people died in mass killings in 2019.

The AP's analysis found that more than 50% of the incidents were family annihilations, which is similar to prior years. Although they are far less common, the 9 public mass shootings during the year were the most deadly type of mass murder, resulting in 73 people's deaths, not including the assailants.

One-third of the offenders died at the scene of the killing or soon after, half from suicides.

About this Dataset

The Associated Press/USA TODAY/Northeastern University Mass Killings database tracks all U.S. homicides since 2006 involving four or more people killed (not including the offender) over a short period of time (24 hours) regardless of weapon, location, victim-offender relationship or motive. The database includes information on these and other characteristics concerning the incidents, offenders, and victims.

The AP/USA TODAY/Northeastern database represents the most complete tracking of mass murders by the above definition currently available. Other efforts, such as the Gun Violence Archive or Everytown for Gun Safety may include events that do not meet our criteria, but a review of these sites and others indicates that this database contains every event that matches the definition, including some not tracked by other organizations.

This data will be updated periodically and can be used as an ongoing resource to help cover these events.

Using this Dataset

To get basic counts of incidents of mass killings and mass shootings by year nationwide, use these queries:

Mass killings by year

Mass shootings by year

To get these counts just for your state:

Filter killings by state

Definition of "mass murder"

Mass murder is defined as the intentional killing of four or more victims by any means within a 24-hour period, excluding the deaths of unborn children and the offender(s). The standard of four or more dead was initially set by the FBI.

This definition does not exclude cases based on method (e.g., shootings only), type or motivation (e.g., public only), victim-offender relationship (e.g., strangers only), or number of locations (e.g., one). The time frame of 24 hours was chosen to eliminate conflation with spree killers, who kill multiple victims in quick succession in different locations or incidents, and to satisfy the traditional requirement of occurring in a “single incident.”

Offenders who commit mass murder during a spree (before or after committing additional homicides) are included in the database, and all victims within seven days of the mass murder are included in the victim count. Negligent homicides related to driving under the influence or accidental fires are excluded due to the lack of offender intent. Only incidents occurring within the 50 states and Washington D.C. are considered.

Methodology

Project researchers first identified potential incidents using the Federal Bureau of Investigation’s Supplementary Homicide Reports (SHR). Homicide incidents in the SHR were flagged as potential mass murder cases if four or more victims were reported on the same record, and the type of death was murder or non-negligent manslaughter.

Cases were subsequently verified utilizing media accounts, court documents, academic journal articles, books, and local law enforcement records obtained through Freedom of Information Act (FOIA) requests. Each data point was corroborated by multiple sources, which were compiled into a single document to assess the quality of information.

In case(s) of contradiction among sources, official law enforcement or court records were used, when available, followed by the most recent media or academic source.

Case information was subsequently compared with every other known mass murder database to ensure reliability and validity. Incidents listed in the SHR that could not be independently verified were excluded from the database.

Project researchers also conducted extensive searches for incidents not reported in the SHR during the time period, utilizing internet search engines, Lexis-Nexis, and Newspapers.com. Search terms include: [number] dead, [number] killed, [number] slain, [number] murdered, [number] homicide, mass murder, mass shooting, massacre, rampage, family killing, familicide, and arson murder. Offender, victim, and location names were also directly searched when available.

This project started at USA TODAY in 2012.

Contacts

Contact AP Data Editor Justin Myers with questions, suggestions or comments about this dataset at jmyers@ap.org. The Northeastern University researcher working with AP and USA TODAY is Professor James Alan Fox, who can be reached at j.fox@northeastern.edu or 617-416-4400.

The deadliest school shooting in the United States as of August 11, 2025, was the Virginia Tech massacre, with 32 fatalities and 23 injuries. The next deadliest school shooting (based on fatalities) was the Sandy Hook Elementary massacre in Newtown, Connecticut, with 27 fatalities. School shootings in the U.S. Mass shootings in the United States have become a disturbingly common occurrence, and sadly, so have school shootings. The Columbine school shooting is perhaps the most famous in the country’s history, and since 1999 (when the shooting occurred), the number of school shootings has only increased. Many measures have been used to try to prevent school shootings, including security guards and metal detectors being deployed in schools, and even the suggestion that teachers be allowed to carry guns in schools. Gun control Gun control in the United States is a sticky issue, since gun ownership is enshrined in the Constitution. Some advocate for stricter gun control laws to try to prevent future mass shootings, while others say that this is unconstitutional. Gun ownership rates in the U.S. are high, with the share of American households owning at least one firearm remaining relatively steady since 1972.

The Washington Post spent a year determining how many children have been affected by school shootings, beyond just those killed or injured. To do that, reporters attempted to identify every act of gunfire at a primary or secondary school during school hours since the Columbine High massacre on April 20, 1999. Using Nexis, news articles, open-source databases, law enforcement reports, information from school websites, and calls to schools and police departments, The Post reviewed more than 1,000 alleged incidents, but counted only those that happened on campuses immediately before, during or just after classes.

Shootings at after-hours events, accidental discharges that caused no injuries to anyone other than the person handling the gun, and suicides that occurred privately or posed no threat to other children were excluded. Gunfire at colleges and universities, which affects young adults rather than kids, also was not counted.

After finding more than 200 incidents of gun violence that met The Post’s criteria, reporters organized them in a database for analysis. Because the federal government does not track school shootings, it’s possible that the database does not contain every incident that would qualify.

To calculate how many children were exposed to gunfire in each school shooting, The Post relied on enrollment figures and demographic information from the U.S. Education Department, including the Common Core of Data and the Private School Universe Survey. The analysis used attendance figures from the year of the shooting for the vast majority of the schools.

The Post’s database is updated regularly as school shootings are reported and as facts emerge about individual cases. The Post is seeking assistance in making the database as comprehensive as possible. To provide information about school shootings since Columbine that fit The Post’s definition, send us an email at schoolshootings@washpost.com.

As of July 14, 2025, there have been a total of 277 school shootings in California since 1966, the most out of any state. Texas had the second highest number of school shootings within this time period, with 237 shootings. The source defines a school shooting as every time a gun is brandished, fired, or a bullet hits school property for any reason, regardless of the number of victims (including zero), time, day or the week, or reason, including gang shootings, domestic violence, shootings at sports games and after hours school events, suicides, fights that escalate into shootings, and accidents.

Context

From GitHub: "Since 2009, at least 177 of America’s schools experienced a shooting. These tragedies are as diverse as our nation, but the depth of trauma is hard to convey. There is no standard definition for what qualifies as a school shooting in the US. Nor is there a universally accepted database. So CNN built our own. We examined 10 years of shootings on K-12 campuses and found two sobering truths: School shootings are increasing, and no type of community is spared."

Acknowledgements

This data was posted by CNN on GitHub. Read the full story. Image from StockSnap.io. Per GitHub, this data is licensed under the MIT license.

Violent deaths and shootings at schools are rare but tragic events with far-reaching effects on the school population and surrounding community. School shootings are of high concern to all those interested in the safety of our nation’s students. This dataset presents data on school-associated violent deaths from the School-Associated Violent Death Surveillance System (SAVD-SS), the National Vital Statistics System and K–12 School Shooting Database (K–12 SSDB) from the Center for Homeland Defense and Security. The SSDB defines “school shootings” as incidents in which a gun is brandished or fired on school property or a bullet hits school property for any reason, regardless of the number of victims, time of day, day of the week, or reason. Data are also available on the type of situation associated with school shootings (including those with and without casualties) as well as on the location and time period of the shootings.

From 1999 to January 2025, *** school shootings were recorded in the United States, *** of which occurred in public schools. Within the provided time period, only ** shootings were recorded in private schools.

Ideas:

1. Chances of the shooter commits suicide after the crime.
2. Average time of occurrences between a 2 digit victim school shooting.
3. Average increase of shootings in those years.

Any other ideas just comment and i'll increase. Thanks!

The graph displays the number of mass shootings in the U.S. by year from 1982 to 2025, with the x-axis representing the years and the y-axis showing the number of incidents per year. The data reveals a significant increase in mass shootings over time, with the highest numbers recorded in 2018, 2022, and 2023, each with 12 incidents. In the early years (1982-2000), mass shootings were relatively low, typically one to three incidents per year. However, after 2012 (7 incidents), the numbers began rising sharply, with 2017 recording 11 incidents and 2019 reaching 10. The data highlights a concerning upward trend in mass shootings over the past two decades.

Between 1970 and June 16, 2020, 175 school shootings were perpetrated by 17-year-olds. 16-year-olds perpetrated the second highest number of school shootings, with 163 shootings.

BackgroundSeveral past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts.MethodsHere we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed). We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event.ConclusionsWe find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001). All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

Firearms are the leading cause of death for minors in the United States and US gun culture is often discussed as a reason behind the prevalence of school shootings. Yet, few studies systematically analyze if there is a connection between the two: Do school shooters show a distinct gun culture? This article studies gun culture in action in school shootings. It studies if school shooters show distinct meanings and practices around firearms prior to the shooting, as well as patterns in access to firearms. To do so, I analyze a full sample of US school shootings. Relying on publicly available court, police, and media data, I combine qualitative in-depth analyses with cross-case comparisons and descriptive statistics. Findings suggest most school shooters come from a social setting in which firearms are a crucial leisure activity and hold meanings of affection, friendship, and bonding. These meanings translate into practices: all school shooters had easy access to the firearms they used for the shooting. Findings contribute to research on firearms and youth violence, public health, as well as the sociology of culture.

Context

To better understand the facts around school shootings a few years ago I went looking for data and found it difficult to come by - often embedded in other datasets or fragmented and unusable. I decided to create my own compilation based on a mashup of the Pah/Amaral/Hagan research on school shootings with the Wikipedia article from 1990 to present.

Content

pah_wikp file: A list of all school shooting incidents from 1990 to present.

Fields:

• Date: date of incident
• City: location of incident
• State: location of incident
• Area Type: urban or suburban (only in Pah dataset)
• School: C = college, HS = high school, MS = middle school, ES = elementary school, - = unknown
• Fatalities: # killed
• Wounded: # wounded (only in Wikipedia dataset)
• Dupe: whether this incident appears in both datasets. Note: only the "Pah" version of the incident is marked.
• Source: Pah or Wikp
• Desc: text description of incident (only in Wikipedia dataset)

cps file: US census data on school populations. Fields should be fairly self explanatory.

Acknowledgements

Thanks to the authors referenced above as well as the Wikipedia contributors!

Inspiration

• Why are school shootings (and death counts) increasing over time?
• How does the risk of being killed in a school shooting compare with other risks?
• Are some schools / cities / states at higher risk?
• Is there a correlation between countermeasures and a decrease in fatalities?
• What else correlates with school shooting risks? In addition to firearms and the people who wield them, is there any clear causality?

github version

Note: the master version of these datasets can be found at https://github.com/ecodan/school-shooting-data.git and is open for community contributions. I'll try to keep this data up-to-date with the github version on at least a monthly basis.

IntroductionFor over two decades school shootings have become a significant concern, especially in the United States. Following a rampage school shooting, extensive resources are devoted to gathering all of the information surrounding the event. To date, few studies have compared completed to averted, or near-miss, school shootings. This study utilized the largest known sample of cases based in the United States in an effort to identify potential targets for prevention.MethodData were derived from the Averted School Violence database of incidents occurring between 1999 and 2020. Statistical analyses were conducted to determine how age, co-conspirator involvement, engagement in leakage warning behavior, and motives – in isolation and in combination – varied between groups.ResultsIn insolation, age, co-conspirator involvement, engagement in leakage warning behaviors, and motives were significantly different between groups. However, when these variables were combined into a logistic regression, co-conspirator involvement, engagement in leakage warning behaviors, and motives involving suicidal intent emerged as statistically significant predictors of group membership. Age no longer differentiated the two types of events.ConclusionThis study demonstrates that regardless of suspect age, threats of school violence must be taken seriously and investigated fully. Further, students reporting their peers’ engagement in shooting-related behaviors (e.g., bringing a gun to school, mapping school, etc.) was one of the most significant predictors that a plot will be thwarted. While perpetrators who planned with others had increased odds of their plot being identified, those acting alone still demonstrated leakage behaviors. If individuals in the school environment are educated regarding warning behaviors, lone perpetrators can still be identified and reported to authorities. The perpetrator’s emotional distress, in particular depressive or suicidal thoughts were also a significant predictor of a completed school shooting. Future research efforts should focus on the development and evaluation of peer training programs to assist in the detection of school shooting warning behaviors.

The graph displays the Top 5 states with the most mass shootings in the U.S. from 1982 to 2025, with the x-axis representing states and the y-axis showing the total number of mass shootings recorded in each state. California leads with 26 mass shootings, followed by Florida and Texas, each with 13 and 14 incidents respectively. Other states with high numbers include Colorado (8), Washington (7). The data shows that mass shootings have occurred across a wide range of states, with some experiencing significantly more incidents than others.

From 2008 to April 25, 2025, the District of Columbia had the highest rate of school shootings nationwide, totaling around **** school shootings per 100,000 residents. Louisiana, Delaware, Maryland, and Alabama rounded out the top five states with the highest school shooting rates relative to their populations. In contrast, there were no school shootings recorded in Montana, Wyoming, New Hampshire, Vermont, and Rhode Island within the provided time period. In addition to K-12 schools and college campuses, gun-related violence in the United States often occurs at workplaces, places of worship, and restaurants and bars. The source defines school shootings as incidents of gun violence which occurred on school property, from kindergartens through colleges/universities, and at least one person was shot, not including the shooter. School property includes, but is not limited to, buildings, fields, parking lots, stadiums and buses. Accidental discharges of firearms are included, as long as at least one person is shot, but not if the sole shooter is law enforcement or school security.