- Iran ranks among the world’s top 20 militaries in terms of personnel, equipment and logistical capacity, according to the Global Firepower index
- Iran’s air force is seen as the weakest branch of its conventional military, with only about 250 combat-capable aircraft
ISTANBUL
In the tense countdown to high-stakes negotiations in Oman, both Washington and Tehran chose to speak first in the language of military power.
The US dispatched carrier strike groups, advanced fighter jets and guided-missile destroyers to the region, a visible show of force meant for pressure and to show readiness to attack.
Iran responded with assertions of its own military capacities, vowing strong retaliation and deploying – just a day before the Muscat talks – its newest medium-range ballistic missile, Khorramshahr-4, inside an underground facility for the first time, a move announced by the state-linked Fars News Agency.
As the parallel displays of strength set a dramatic backdrop for diplomacy, the message from Iran has been clear: its military doctrine remains rooted in deterrence, missile power and asymmetric warfare rather than conventional force projection.
According to the Global Firepower index, Iran ranks among the world’s top 20 militaries in terms of personnel, equipment and logistical capacity.
Here is a closer look at Iran’s military strength and capabilities:
Personnel
Iran maintains one of the largest standing armed forces in the Middle East.
The Military Balance 2025 report, published by the International Institute for Strategic Studies (IISS), estimates that Iran has around 610,000 active-duty personnel.
This includes roughly 350,000 troops in the regular army and about 190,000 members of the Islamic Revolutionary Guard Corps (IRGC), the powerful parallel force responsible for missiles, drones and regional operations.
The breakdown also includes nearly 18,000 personnel in the navy, 37,000 in the air force and around 15,000 in air defense units, while gendarmerie and paramilitary forces number approximately 40,000.
In addition, Iran is believed to have some 350,000 reservists, who include army veterans and volunteer forces.
Ballistic missiles and drones
Missiles and unmanned systems form the backbone of Iran’s defense doctrine.
The Center for Strategic and International Studies (CSIS) says Iran possesses the largest and most diverse missile arsenal in the Middle East, with thousands of ballistic and cruise missiles ranging from a few hundred kilometers to as far as 2,000-2,500 kilometers (over 1,240-1,550 miles).
Some of these systems are capable of reaching Israel and parts of southeastern Europe, the organization says.
Prior to last year’s 12-day war with Israel, Iran’s ballistic missile inventory was estimated at between 2,500 and 3,000. Analysts believe that arsenal was reduced by roughly half during the conflict.
Iran’s top military official, Maj. Gen. Abdolrahim Mousavi, said this week that the country had strengthened its deterrence by upgrading domestically manufactured ballistic missiles. He added that Iran had shifted its military doctrine from defensive to offensive by adopting a policy of asymmetric warfare.
In October, CNN reported that Iran purchased sodium perchlorate from China to replenish missile stocks that had been depleted during the conflict with Israel.
According to the IISS, Iran’s missile forces compensate for its weak air force by enabling long-range strikes through short- and medium-range ballistic missiles, land-attack cruise missiles, and unmanned aerial vehicles (UAVs).
Among the most prominent missiles in Iran’s arsenal is the Khorramshahr-4, with a range of 2,000 kilometers (over 1,220 miles) and a warhead weighing 1,500 kilograms (over 3,305 pounds).
Other systems include the Ghadr-110 (2,000 km range), the Haj Qassem (1,400 km), the Emad (1,700 km with 500-meter accuracy), and the Qasem Basir, a solid-fuel missile capable of traveling 1,200 km. The short-range Zolfagar missile has a range of 700 km.
During last year’s conflict with Israel, the IRGC announced it had used the Sejjil-2 for the first time, describing it as “a ballistic missile with a range of 2,000 kilometers, armed with a warhead of exceptionally destructive power.” It also claimed to have deployed the hypersonic Fattah missile, which has a range of 1,400 km.
Over the course of that war, Iran is believed to have launched around 550 ballistic missiles and approximately 1,000 drones at Israeli targets.
Iran has invested heavily in unmanned combat aerial vehicles, particularly the Shahed and Mohajer series. The Shahed drones have also been used extensively by Russia in Ukraine, according to CSIS.
This week, the US military said an American F-35 fighter jet shot down an Iranian Shahed-139 drone that was flying toward a US aircraft carrier “with unclear intent.”
The Iranian military also claims to operate a network of underground missile bases – often referred to as “missile cities” – scattered across the country.
Ground forces
On land, Iran fields a large but largely conventional force.
The IISS estimates that the regular army alone has around 350,000 troops, supported by more than 1,500 main battle tanks, including a mix of T-72s, locally produced Zulfiqar tanks, and older US-made models.
The army also operates hundreds of infantry fighting vehicles and armored personnel carriers, along with nearly 7,000 artillery systems ranging from towed guns to multiple rocket launchers.
Much of this hardware dates back decades and consists of upgraded US, Soviet and Chinese designs, making Iran’s ground forces more suited for territorial defense and prolonged attrition warfare than for rapid offensive operations, according to analysts.
Air force
Iran’s air force is widely regarded as the weakest branch of its conventional military.
Despite having roughly 37,000 personnel, the country operates only about 250 combat-capable aircraft, according to the IISS.
Many of these planes predate the 1979 Islamic Revolution, including aging F-4 Phantoms, F-5 Tigers and a small number of F-14 Tomcats.
Analysts say sanctions have made maintenance and modernization increasingly difficult.
Iran’s air force is “largely made up of aging Cold War designs originating mostly from the US, with some Soviet models and a single French fighter rounding out the fleet,” according to defense review Warpower: Iran.
“Spares and lack of foreign support have limited modernization of these systems while attempts have been made by local industry to replicate some of the offerings – namely the American Northrop F-5 Tiger lightweight fighter series,” it added.
Navy
At sea, Iran has adopted an explicitly asymmetric strategy, according to the IISS.
“Although Iran’s naval force focuses on asymmetric approaches, such as the use of mines, anti-ship missiles, speedboats and small submarines, the service has shown interest in blue water operations and power projection,” it added.
Rather than relying on large warships, the Islamic Republic of Iran Navy (IRIN) operates more than 100 small fast-attack craft armed with anti-ship missiles and rockets, designed to swarm larger vessels in the confined waters of the Gulf.
Global Firepower estimates that Iran’s navy possesses 109 assets, including 25 submarines, 21 patrol vessels, seven frigates, three corvettes, and one mine-warfare ship.
Military spending
Iran’s military budget remains modest compared to regional rivals.
According to data from the Stockholm International Peace Research Institute (SIPRI), Iran spent $7.9 billion on defense in 2024 – 10% less than in 2023 but still 21% higher than in 2015.
“The year-on-year decrease was mainly due to the effects of persistently high inflation on Iranian spending, partly stemming from US economic sanctions on Iran, which have had an impact on oil exports, Iran’s main source of export revenue,” SIPRI said.
However, Iranian media reported in December that the government approved a 145% increase in defense and security allocations for the coming year, bringing proposed spending to around $9.2 billion.
