There were 449,344 active duty U.S. Army members in 2023. This amount represents a slight decrease in comparison to the number recorded in the previous year. Overall, there were 1.27 million active duty U.S. Department of Defense members, including officers and enlisted personnel in 2023.

Throughout the 19th century, the share of military personnel employed by the United States government was below 0.2 percent of the total population in most years. There were noticeable spikes in enlistments and conscriptions during the American Civil War (1861-65), the First World War (1917-18*), and Second World War (1941-45*), as well as smaller increases during the Mexican-American War (1946-48) and the Spanish-American War (1898), but figures were generally much lower than the post-WWII era.

Following the Second World War, the United States abandoned many of its isolationist positions as it sought to become the world's leading superpower. This involved stationing millions of troops in overseas bases during the Cold War, in strategically important locations such as West Germany, Japan, and Taiwan. Additionally, involvement in conflicts such as the Korean War (1950-1953) and Vietnam War (1964-1973*) kept military employment high, usually between 1-2 percent until the 1970s. Figures remained just below the one percent mark until the 1990s, when the end of the Cold War and the growing influence of technology in conventional warfare saw a decrease in demand for many traditional combat roles. Despite U.S. involvement in a number of overseas conflicts in the 21st century, military personnel represented less than 0.5 percent of the total population in most years between 2000 and 2016.

The U.S. Army remains the largest branch of the American military, with 449,344 active duty personnel in 2023. While the Army leads in numbers, the newly established Space Force had just 8,879 active duty members, highlighting the evolving nature of modern warfare and the increasing importance of space-based capabilities. Confidence in military remains high Despite fluctuations in force size, public trust in the U.S. military remains strong. In 2024, 61 percent of Americans expressed a great deal or quite a lot of confidence in the armed forces, a slight increase from the previous year. While a slightly higher share of Republicans have shown more confidence in the military, trust in the institution remains high across party lines. Global commitments The United States continues to invest heavily in its military capabilities, with defense spending reaching 916.02 billion U.S. dollars in 2023. This substantial budget supports not only domestic defense needs but also enables the U.S. to respond to global crises, as evidenced by the over 40 billion euros in military aid provided to Ukraine following Russia's invasion. The high level of spending, which translates to about 2,220 U.S. dollars per capita.

The graph illustrates the number of personnel in each branch of the U.S. Military for the year 2025. The x-axis lists the military branches: Army, Navy, Marine Corps, Air Force, Space Force, and Coast Guard. The y-axis represents the number of personnel, ranging from 41,477 to 449,265. Among the branches, the Army has the highest number of personnel with 449,265, followed by the Navy with 333,794 and the Air Force with 317,675. The Marine Corps and Coast Guard have 168,628 and 41,477 personnel, respectively. The data is displayed in a bar graph format, effectively highlighting the distribution of military personnel across the different branches.

At the end of the fiscal year of 2024, it is estimated that there will be ** Generals serving the United States Army, and a total of ******* enlisted personnel. Military personnel The military departments in the United States are: the U.S. Army, the U.S. Navy, the U.S. Air Force, the U.S. Marine Corps, and the U.S. Coast Guards. The President of the United States is the military’s overall head and forms the military policy with the U.S. Department of Defense. The U.S. military is one of the largest militaries in term of number of personnel. The largest branch of the United States Armed Forces is the United States Army. The United States Army is responsible for land-based military operations. The active duty U.S. Army personnel number has decreased from 2010 to 2021. In 2010, there were ******* active duty U.S. Army members, as compared to ******* in 2021. The number of active duty U.S. Navy personnel has decreased slowly over the past 20 years. In 2021, there were ******* active duty Navy members in the United States Navy. The United States Navy personnel are enlisted sailors, commissioned officers, and midshipmen. Sailors have to take part in Personnel Qualification Standards, to prove that they have mastered skills. The United States Air Force is the aerial warfare service branch of the United States. The active duty U.S. Air Force personnel numbers also decreased between 1995 and 2015, although has started to increase slightly since 2015. The number decreased again in 2021, when the Air Force had ******* personnel.

This graph shows the total number of active duty U.S. military personnel by service branch as of 2010. At this time there were 323,139 military personnel in the Navy and 329,640 personnel in the Air Force.

Russia military size for 2020 was 1,454,000, a 0% increase from 2019.

<ul style='margin-top:20px;'>

<li>Russia military size for 2019 was <strong>1,454,000</strong>, a <strong>0% increase</strong> from 2018.</li>
<li>Russia military size for 2018 was <strong>1,454,000</strong>, a <strong>0% increase</strong> from 2017.</li>
<li>Russia military size for 2017 was <strong>1,454,000</strong>, a <strong>0% increase</strong> from 2016.</li>
</ul>Armed forces personnel are active duty military personnel, including paramilitary forces if the training, organization, equipment, and control suggest they may be used to support or replace regular military forces.

Armed forces personnel, total in World was reported at 27406000 in 2020, according to the World Bank collection of development indicators, compiled from officially recognized sources. World - Armed forces personnel, total - actual values, historical data, forecasts and projections were sourced from the World Bank on July of 2025.

Historical chart and dataset showing China military size by year from 1985 to 2020.

As of May 2025, China had the largest armed forces in the world by active duty military personnel, with about *********** active soldiers. India, the United States, North Korea, and Russia rounded out the top five largest armies. Difference between active and reserve personnel Active personnel, also known as active duty in the United States and active service in the United Kingdom, are those individuals whose full-time occupation is being part of a military force. Active duty contrasts with a military’s reserve force, which are individuals who have both a military role and a civilian career. The number of active duty forces in the U.S. is much larger than its reserve membership. What is the strongest army? The strength of a country’s armed forces is not only determined by how many personnel they maintain, but also the number and quality of their military equipment. For example, looking only at personnel does not factor in the overwhelmingly higher number of nuclear warheads owned by Russia and the United States compared to other countries. One way to answer this question is to look at the total amount of money each country spends on their military, as spending includes both personnel and technology. In terms of countries with the highest military spending, the United States leads the world with an annual budget almost ***** times larger than second-placed China.

India military size for 2020 was 3,068,000, a 0.76% increase from 2019.

<ul style='margin-top:20px;'>

<li>India military size for 2019 was <strong>3,045,000</strong>, a <strong>0.61% increase</strong> from 2018.</li>
<li>India military size for 2018 was <strong>3,026,500</strong>, a <strong>0.15% decline</strong> from 2017.</li>
<li>India military size for 2017 was <strong>3,031,000</strong>, a <strong>1.68% increase</strong> from 2016.</li>
</ul>Armed forces personnel are active duty military personnel, including paramilitary forces if the training, organization, equipment, and control suggest they may be used to support or replace regular military forces.

Historical chart and dataset showing U.K. military size by year from 1985 to 2020.

Historical chart and dataset showing Japan military size by year from 1985 to 2020.

The 2012 US Army Anthropometric Survey (ANSUR II) was executed by the Natick Soldier Research, Development and Engineering Center (NSRDEC) from October 2010 to April 2012 and is comprised of personnel representing the total US Army force to include the US Army Active Duty, Reserves, and National Guard. The data was made publicly available in 2017. In addition to the anthropometric and demographic data described below, the ANSUR II database also consists of 3D whole body, foot, and head scans of Soldier participants. These 3D data are not publicly available out of respect for the privacy of ANSUR II participants. The data from this survey are used for a wide range of equipment design, sizing, and tariffing applications within the military and has many potential commercial, industrial, and academic applications.These data have replaced ANSUR I as the most comprehensive publicly accessible dataset on body size and shape. The ANSUR II dataset includes 93 measurements from over 6,000 adult US military personnel, comprising 4,082 men (ANSUR_II_MALE_Public.csv) and 1,986 women (ANSUR_II_FEMALE_Public.csv).

The ANSUR II working databases contain 93 anthropometric measurements which were directly measured, and 15 demographic/administrative variables.

Much more information about the data collection methodology and content of the ANSUR II Working Databases may be found in the following Technical Reports, available from theDefense Technical Information Center (www.dtic.mil) through:

a. 2010-2012 Anthropometric Survey of U.S. Army Personnel: Methods and Summary
Statistics. (NATICK/TR-15/007)
b. Measurer’s Handbook: US Army and Marine Corps Anthropometric Surveys,
2010-2011 (NATICK/TR-11/017)

Poland military size for 2020 was 189,000, a 0% increase from 2019.

<ul style='margin-top:20px;'>

<li>Poland military size for 2019 was <strong>189,000</strong>, a <strong>3.91% decline</strong> from 2018.</li>
<li>Poland military size for 2018 was <strong>196,700</strong>, a <strong>2.98% increase</strong> from 2017.</li>
<li>Poland military size for 2017 was <strong>191,000</strong>, a <strong>7.06% increase</strong> from 2016.</li>
</ul>Armed forces personnel are active duty military personnel, including paramilitary forces if the training, organization, equipment, and control suggest they may be used to support or replace regular military forces.

In 2023, there were around 1.11 million active duty U.S. Armed Forces personnel stationed within the United States. In that year, there were 156,418 U.S. Armed Forces personnel stationed in California, the most of any state.

U.S. military spending/defense budget for 2022 was 876.94 billion US dollars, a 8.77% increase from 2021.

<ul style='margin-top:20px;'>

<li>U.S. military spending/defense budget for 2021 was <strong>806.23 billion US dollars</strong>, a <strong>3.58% increase</strong> from 2020.</li>
<li>U.S. military spending/defense budget for 2020 was <strong>778.40 billion US dollars</strong>, a <strong>6% increase</strong> from 2019.</li>
<li>U.S. military spending/defense budget for 2019 was <strong>734.34 billion US dollars</strong>, a <strong>7.6% increase</strong> from 2018.</li>
</ul>Military expenditures data from SIPRI are derived from the NATO definition, which includes all current and capital expenditures on the armed forces, including peacekeeping forces; defense ministries and other government agencies engaged in defense projects; paramilitary forces, if these are judged to be trained and equipped for military operations; and military space activities. Such expenditures include military and civil personnel, including retirement pensions of military personnel and social services for personnel; operation and maintenance; procurement; military research and development; and military aid (in the military expenditures of the donor country).

Historical chart and dataset showing Egypt military size by year from 1985 to 2020.

List of Army personnel in the world, and the population of the respective country. The data is extracted and scrapped from 1. https://worldpopulationreview.com/country-rankings/military-size-by-country 2. https://en.wikipedia.org/wiki/List_of_countries_by_number_of_military_and_paramilitary_personnel

***************************************************************************************** April 29, 2025: STARRS - Longitudinal Study Wave 4 (LSW4) data released ***************************************************************************************** The Army Study to Assess Risk and Resilience in Servicemembers (STARRS) is an extensive study of mental health risk and resilience among military personnel. Army STARRS consists of eight separate but integrated epidemiologic and neurobiologic studies. Survey data for three of the Army STARRS study components are available via Secure Dissemination or via the ICPSR Virtual Data Enclave: New Soldier Study (NSS); All Army Study (AAS) and Pre-Post Deployment Study (PPDS). Also available are data for the STARRS-Longitudinal Study (STARRS-LS), which are follow-up surveys conducted with Army STARRS participants from AAS, NSS and PPDS studies. Lastly, baseline administrative data from the Army/Department of Defense (DoD) and blood sample flags for Soldiers who had blood drawn as a part of their participation in NSS or PPDS are available. The AAS component of Army STARRS assesses soldiers' psychological and physical health, events encountered during training, combat, and non-combat operations, and life and work experiences across all phases of Army service. The AAS data includes data on soldiers' psychological resilience, mental health, and risk for self-harm. The NSS data are drawn from new soldiers who have just entered the Army. The data contain information on soldier health, personal characteristics, and prior experiences. Results from a series of neurocognitive tests are also included in the NSS data. The PPDS data are drawn from active duty soldiers who were interviewed at four points in time: 3-4 months prior to deployment to Afghanistan; within 1-2 weeks after return from deployment; 1-3 months after return from deployment; and 9-12 months after return from deployment. The PPDS data contain information on soldiers' psychological resilience, mental health, deployment experiences, and risk for self-harm. The STARRS-LS data are from multiple follow-up interviews with individuals who previously participated in the AAS, NSS and PPDS study components of Army STARRS. STARRS-LS data contain follow-up information on soldiers' and veterans' physical and mental health, resilience and risk for self-harm, military and employment status, deployment experience, and personal characteristics as they move through their Army careers and after they leave the Army.