Which Countries Have the Largest Militaries, and Why

India has the largest military in the world by total armed forces personnel, with about 3.07 million people under arms, followed by China with about 2.54 million and North Korea with about 1.47 million, according to the World Bank's World Development Indicators for 2020, which are compiled from the International Institute for Strategic Studies (IISS) Military Balance. Russia (1.45 million) and the United States (1.40 million) complete the top five. The World Bank figure counts active-duty troops plus paramilitary forces trained and equipped to support or replace them, which is why India, with its large border and armed police forces, edges out China. Counting only regular active-duty soldiers, China's People's Liberation Army, at roughly 2 million, is the biggest single force.

These ten countries account for about 13.8 million of the roughly 27.4 million armed forces personnel the World Bank counted worldwide in 2020, around half of the global total. They are not a random selection. Four forces put countries on this list, often in combination: a very large population, a tense or disputed frontier, a law that makes young men serve, and a history as a great power. The per-1,000 column in the table shows which of these is doing the work in each case.

The source matters too. The IISS, a London think tank, publishes The Military Balance every year and splits each country's forces into three columns: active military, reserves and paramilitary. The World Bank takes the active column and adds only those paramilitary units whose training, organisation and equipment suggest they could fight alongside or instead of the regular forces. Reservists are left out entirely, which keeps South Korea, with millions of reservists but about 569,000 personnel on the World Bank measure, out of the top ten. Rankings that count reserves look very different, so any comparison should say which column it uses.

Population: India, China, Indonesia and Pakistan

The simplest explanation is scale. India (about 1.40 billion people in 2020) and China (about 1.41 billion) could field the world's biggest armies while committing only about two people in every thousand. China's army has in fact been shrinking for decades: it was cut by a million between 1985 and 1987, by another 500,000 in the late 1990s, and by further rounds announced in 2003 and 2005, taking the PLA from about 2.5 million to around 2 million. The money saved has gone into the navy, air force and Rocket Force rather than infantry. The World Bank total for China fell from 2,843,000 in 2015 to 2,535,000 in 2020, which is how India moved into first place.

India's figure counts some of its paramilitary forces, such as the Central Armed Police Forces, alongside the Army, Navy and Air Force. The Indian Armed Forces on their own have more than 1.4 million active personnel, and the Army is often described as the world's largest volunteer army, with no conscription. Indonesia, the fourth most populous country, and Pakistan, the fifth, reach the top ten on the same logic of numbers. Indonesia's regular forces numbered about 404,500 in 2023, and the World Bank's larger total also takes in paramilitary formations such as the police Mobile Brigade Corps, spread across an archipelago of thousands of islands.

Frontlines: the Korean DMZ, the Line of Control and the Line of Actual Control

Population alone does not explain North Korea, which has about 26 million people and yet the third-largest force on the list, 56 soldiers for every 1,000 inhabitants. Its army exists because the Korean War never formally ended. The Korean Armistice Agreement of July 1953 created the Demilitarized Zone, a strip about 250 km long and 4 km wide across the peninsula, and both sides of it remain among the most heavily armed places on Earth. Pyongyang treats South Korea's forces and the United States Forces Korea as its main adversaries, and it keeps an army sized for that confrontation.

South Asia has two such lines. The Line of Control divides the parts of the former princely state of Jammu and Kashmir administered by India and by Pakistan; it was set in the 1972 Simla Agreement after the 1971 war and is not a recognised international boundary. Further east, the Line of Actual Control separates Indian-held and Chinese-held territory after the 1962 Sino-Indian War, with India claiming Aksai Chin and China claiming Arunachal Pradesh, which it calls Zangnan. India and Pakistan fought wars in 1947, 1965, 1971 and 1999, and each keeps large forces facing the other. China, which shares land borders with 14 countries, tied with Russia for the most in the world, has frontiers to watch in every direction.

Conscription laws in North Korea, Egypt, Iran and Brazil

A draft turns a country's age structure directly into troop numbers. North Korea conscripts men at 17 and extended service from eight to ten years in 1993, which is the main reason its ratio is more than five times Russia's. Egypt, seventh on the list, makes men without a university degree serve three years, those with a secondary-school certificate two, and graduates one year as enlisted men or three as reserve officers. Iran requires about 18 months to two years of service from men at 18, and the General Staff decides whether a conscript joins the regular army, the Islamic Revolutionary Guard Corps or the police. Iran is also unusual in running two parallel militaries, the army and the IRGC, founded by Ayatollah Khomeini in May 1979.

Egypt's large army is also a product of its history. Its forces fought Israel in 1948, in the Six-Day War of 1967 and in the Yom Kippur War of 1973, took part in the 1991 Gulf War, and have been engaged against an insurgency in Sinai in recent years. Since the 1952 revolution that ended the monarchy, the military has dominated Egyptian politics and much of its economy, and conscription is seen as one of the ways it binds together recruits from every class. Egypt's World Bank total hardly moved between 2015 (835,500) and 2020 (836,000), a sign of a force sized by law and tradition rather than by any single crisis.

Brazil keeps conscription on the books, with an obligation of 10 to 12 months for men from the age of 18, and volunteers may join from 17. With about 334,500 active-duty troops, it has the largest armed forces in Latin America and the second largest in the Americas after the United States. Pakistan shows the opposite case: the constitution allows conscription in wartime, but it has never been used because volunteers have always been plentiful. In 2024 it had about 660,000 active personnel and 291,000 in paramilitary forces such as the Civil Armed Forces.

Reach and inheritance: the United States and Russia

The United States is the only country in the top five without either a huge population or a hostile land frontier. Its force of about 1.4 million, all volunteers since the draft ended in 1973, is sized for commitments far from home: forces in Europe under NATO, in South Korea and Japan, and a navy and air force built to operate across oceans. Measured by spending rather than headcount it ranks first in the world, and it fields fewer, more expensive units than China or India.

Russia inherited the largest share of the Soviet armed forces. It set up its own military by decree on 7 May 1992 and cut the Soviet-era strength of 2.7 million to 2.1 million by 1994 and to about 1 million by 2000. Before 2022 it was estimated at about 900,000 regular personnel, and its 2020 World Bank figure of 1.45 million includes large internal-security formations. Russia still requires one year of military service from most men, and on 1 January 2024 it widened the draft age from 18–27 to 18–30, even as it has tried since the early 2000s to move combat units onto professional contracts.

What has changed since the 2020 count

Personnel numbers move quickly, and the 2020 snapshot is already dated in two places. After the full-scale invasion of Ukraine in 2022, Russia set out to raise its authorised military strength from 1.15 million to 1.5 million, and the defence ministry has reportedly recruited 400,000 to 500,000 soldiers a year during the war. Ukraine, outside the 2020 top ten, has mobilised on a scale that no peacetime table captures. Elsewhere the order is more stable: Pakistan's active strength in 2024 was close to its 2020 level, Egypt's total barely changed between 2015 and 2020, and China continues to trade manpower for technology.

Headcount is also only one measure of size. Reserves swell some forces enormously, especially in South Korea and North Korea, while budgets, equipment and nuclear arsenals rank countries very differently; the strategic side of the picture is covered in the countries with the most nuclear weapons. The draft rules that fill several of these armies are compared in our guide to countries with mandatory military service, and for the opposite end of the scale, see the countries that have no military at all.