Iran has a population of approximately 90 million people as of 2025, making it the 17th most populous country in the world and the second most populous in the Middle East after Egypt. Spread across a rugged landscape between the Caspian Sea and the Persian Gulf, Iran's people represent one of the most fascinating demographic stories of the modern era — a nation that swung from explosive growth to one of the steepest fertility declines ever recorded.
How Many People Live in Iran?
Iran's population stands at roughly 90 million in 2025. To put that in perspective, it is home to more people than Germany, the United Kingdom, or France, yet fewer than neighboring countries do not come close — Turkey and Egypt are its nearest regional rivals in size. Iran ranks 17th globally, sitting just behind Vietnam and the Democratic Republic of the Congo and ahead of Turkey.
With a land area of about 1.65 million square kilometers, Iran has a population density of roughly 55 people per square kilometer. That figure is modest, but it conceals a stark reality: vast stretches of the central plateau are arid desert, so the population is heavily concentrated in the cooler, wetter northwest and along the Caspian coast, leaving the interior almost empty.
Population Growth and the Great Fertility Decline
Iran's population is currently growing at an annual rate of about 0.93%, a moderate pace by global standards and a dramatic fall from its historic peak. During the 1980s, in the midst of the Iran-Iraq War, the growth rate soared to nearly 3.9% — among the highest on Earth. Ayatollah Khomeini encouraged large families to build what he called an "army of 20 million," and the country experienced an enormous baby boom.
The reversal that followed is one of the most studied episodes in demographics. In 1989 the government launched a remarkably effective family planning program, offering free contraception, mandatory marriage counseling, and public health campaigns. The total fertility rate collapsed from around 6.5 children per woman in the mid-1980s to roughly 2.0 by 2000 — the fastest such decline ever documented. Today the rate hovers near 1.7, below the replacement level needed to keep the population stable.
Now the pendulum has swung again. Concerned about an aging society and shrinking future workforce, Iranian leaders have urged families to have more children and rolled back many of the earlier policies. Whether this push succeeds remains an open question, as economic pressures keep many young couples cautious about raising large families.
The Largest Cities
Iran is a highly urbanized nation, with roughly three-quarters of its people living in cities. The three largest are Tehran, Mashhad, and Isfahan.
- Tehran: The capital and largest city, with about 9 million residents in the city proper and roughly 15 million in its wider metropolitan area. Nestled against the Alborz Mountains, it is the political, economic, and cultural heart of the country.
- Mashhad: The second-largest city, home to around 3.3 million people. As Iran's holiest city, it surrounds the shrine of Imam Reza, which draws more than 20 million pilgrims each year.
- Isfahan: A city of roughly 2 million, celebrated for its breathtaking Safavid-era architecture, tiled mosques, and historic bridges. A Persian saying calls it "half the world."
Other major centers include Karaj, Shiraz, and Tabriz, each anchoring distinct cultural regions of the country.
Demographics and Society
Iran is ethnically and linguistically diverse. Persians make up about 61% of the population, with significant minorities of Azerbaijanis (around 16%), Kurds (roughly 10%), and Lurs (about 6%), alongside smaller Arab, Baloch, and Turkmen communities. Persian, or Farsi, is the official language, though many citizens speak regional tongues at home.
Religion is overwhelmingly Islam: about 99% of Iranians are Muslim, with Shia Islam dominant at roughly 89% and Sunnis accounting for most of the remainder. Iran is governed as an Islamic republic, a system established after the 1979 revolution.
The legacy of the 1980s baby boom means Iran still has a relatively youthful population, but it is aging fast. The median age has climbed to about 32 years, and the share of elderly citizens is rising steadily. Education has transformed dramatically: literacy has soared from 37% in 1976 to over 97% today, and more women than men are now enrolled in Iran's universities — a quiet social revolution within a single generation. For a fuller picture of the country's geography and history, see our iran country guide.
Frequently Asked Questions
What is the population of Iran in 2025?
Iran's population is approximately 90 million people as of 2025, ranking it as the 17th most populous country in the world and the second largest in the Middle East after Egypt.
Is Iran's population growing or shrinking?
It is still growing, but slowly, at about 0.93% per year. The fertility rate of around 1.7 children per woman is below replacement level, so without policy changes or migration, growth is expected to slow further and eventually reverse in the coming decades.
What is the largest city in Iran?
Tehran is by far the largest city, with about 9 million residents in the city itself and roughly 15 million across its metropolitan area. It serves as Iran's capital and its political, economic, and cultural center.
What ethnic groups live in Iran?
Persians form the majority at around 61%, followed by Azerbaijanis (about 16%), Kurds (about 10%), and Lurs (about 6%), with smaller Arab, Baloch, Turkmen, and other communities making Iran a genuinely multiethnic society.