Comparison of Iran vs. Israel's Military Strength: Israel launched attacks on Iranian military sites on Saturday, October 26, citing retaliation for Tehran's rocket attack on Israel on October 1, marking a further escalation in the conflict between the two Middle East rivals.

The Israeli military said it had achieved its goals and warned Iran of retaliation. Meanwhile, a semi-official Iranian news agency promised a “proportionate response” to Israel’s actions.

The outcome of a hypothetical conflict between Iran and Israel is uncertain because both nations have significant but different military strengths, strategies and regional alliances that make a head-to-head duel difficult to predict.

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Below is an overview of both countries' military might and air defense systems:

IRAN

Total military personnel: Iran's total military personnel are estimated at about 610,000, with about 350,000 active members (of which the regular army includes 230,000 and the Islamic Revolutionary Guard Corps (IRGC) the rest).

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Arsenal of ballistic missiles: Iran has an extensive arsenal of ballistic missiles capable of reaching various parts of Israel, as well as cruise missiles and drones. While not as technologically advanced as Israel's arsenal, Iran's missile capabilities provide significant range and threat. Iran has more than 3,500 surface-to-surface missiles, some of which carry half-ton warheads. However, the number of people able to reach Israel could be lower.

• Tehran also has the domestically produced Bavar-373 surface-to-air missile platform and the Sayyad and Raad defense systems.

Fighter aircraft: Iran has a squadron of nine F-4 and F-5 fighter jets, a squadron of Russian Sukhoi-24 jets and some MiG-29, F7 and F14 aircraft, IISS said. The commander of Iran's air force said in April that the Sukhoi-24s were in “best preparation” to counter a possible Israeli attack. But Iran's reliance on the Sukhoi-24, first developed in the 1960s, underscores the relative weakness of its air force.

• Iran also has unmanned aircraft that fly to targets and explode them. Analysts estimate the company's drone arsenal to be in the few thousand.

Tank: Iran reportedly operates around 2,842 tanks, a mix of older Soviet-era models and locally upgraded versions, with an emphasis on numbers rather than cutting-edge technology.

Nuclear weapons: Iran currently has no nuclear weapons, but has an extensive nuclear program, initially aimed at civilian energy purposes. However, given uranium enrichment and other possibilities, concerns remain about its potential to develop nuclear weapons.

ISRAEL

Total military personnel: Approximately 645,000, including approximately 169,500 active members and approximately 465,000 reservists.

Fighter aircraft: Israel has an advanced US-supplied air force with hundreds of F-15, F-16 and F-35 multirole jet fighters. These played a role in the downing of Iranian drones in April, when Iran fired explosive drones and fired missiles at Israel in its first direct attack on Israeli territory.

• The Air Force lacks long-range bombers, although a smaller fleet of repurposed Boeing 707s serve as tankers that could allow its fighters to reach Iran for pinpoint missions.
• The Israeli Air Force demonstrated its ability to strike targets at long range in July when its fighter jets struck areas near the Yemeni port of Hodeidah in retaliation for a Houthi drone attack in Tel Aviv.

Drones: Israel is a pioneer in drone technology and has pilotless Heron aircraft that can fly for more than 30 hours, enough for long-distance missions. Its loitering Delilah munitions have an estimated range of 250 km – far less than the Gulf region where Iran is located, although the Air Force could close the gap by delivering one of the munitions closer to the Iranian border.

Rockets: It is widely believed that Israel has developed long-range surface-to-surface missiles, but this is neither confirmed nor denied.

• A multi-layered air defense system developed with U.S. help after the 1991 Gulf War gives Israel several additional options to shoot down Iranian long-range drones and missiles.
• Israel's defense systems, including the Iron Dome, David's Sling and Arrow, are extremely effective at intercepting incoming rockets, rockets and drones. The Israeli systems are designed to be integrated with corresponding U.S. interceptors in the region to provide coalition-strength defense.

Tank: Israel deploys around 1,650 tanks and attaches great importance to quality. Most are Merkava models, known for their advanced armor, firepower and defense systems tailored to combat in the Middle East.

Nuclear weapons: Organizations such as the Federation of American Scientists estimate that Israel has around 80 to 90 nuclear warheads.