Muslims are world’s fastest-growing religious group; Jews far below pre-Holocaust numbers

Between 2010 and 2020, the global Jewish population grew by fewer than one million people – a 6% increase – significantly slower than the 12% growth rate of the world’s overall population, according to a new Global Religious Landscape report released Monday by the Pew Research Center.

The Jewish growth rate mirrors that of the Christian population, which rose from 2.1 billion to 2.3 billion over the same period. In contrast, the Muslim population expanded at a much faster pace (by 21%), growing from 1.7 billion to 2.0 billion, making it the world’s fastest-growing religious group.

Of the Jewish population, about 46%, or 6.78 millions, lived in Israel, 39% or 5.7 millions, in the United States, and the rest in other areas of the world, including 3.1% in France, 2.4% in Canada and 2% in the United Kingdom – with estimated populations of 460,000, 350,000, and 300,000, respectively.

The Pew report highlights that, nearly 80 years after the Holocaust, in 2020, the global Jewish population still fell short of its pre-World War II level, 14.78 million compared to an estimated 16.6 million in 1939.

According to Sergio DellaPergola, Professor Emeritus and former Chairman of the Hebrew University’s Harman Institute of Contemporary Jewry, it will take another 10 to 20 years for the Jewish population to recover to its pre-Holocaust size fully.

“It will mark a historic moment,” he told The Times of Israel over a video interview.

DellaPergola previously served on the academic advisory committees for two major Pew studies on American Jews, published in 2013 and 2020. Although he did not contribute directly to the Global Religious Landscape report, its authors noted that they relied extensively on data he compiled for the annual “World Jewish Population” chapters in the American Jewish Year Book.

The Pew report analyzes data from 2010 to 2020, but DellaPergola has already released updated figures covering up to January 1, 2024.

“The general trends remained the same, even though some numbers, especially for Israel, have increased,” he said. He explained that the Jewish population in Israel grows by about 100,000 every year.

DellaPergola has been following global Jewish population trends since the 1980s.

According to the demographer’s most recent estimates, as of the beginning of 2024, there were approximately 15.7 million Jewish individuals worldwide.

Who is a Jew?

However, DellaPergola noted that his estimate and Pew’s cannot be directly compared, as they rely on slightly different definitions of who is considered Jewish.

“When we tackle the question of assessing how many Jews live in the world, the way we define who is a Jew is always crucial,” he said.

In his reports, DellaPergola provides four different definitions – and therefore numbers.

The Core Jewish population, estimated at 15.7 million in 2024, comprises individuals who identify exclusively as Jewish, whether in religious, cultural, or ethnic terms.

Additional definitions include children of at least one Jewish parent (18.8 million in 2024), and individuals with Jewish background or connections – including non-Jewish household members – estimated at 21.8 million.

Finally, some 24.8 million were eligible to move to Israel under the Law of Return (all Jews, their children, grandchildren, and respective spouses).

“Pew’s core mission is to study religious trends, so they define Jewish identity primarily through a religious lens, excluding individuals who identify as Jews with no religion,” DellaPergola explained.

“Interestingly, in this report, they applied a much narrower definition than in the previous studies on American Jews,” he added.

Indeed, the Pew authors clarified that this survey included only those who self-identified as Jewish by religion. In contrast, the earlier reports on American Jews counted individuals with a Jewish parent or those who identified as Jewish for cultural, ethnic, or other non-religious reasons.

For Israel, the Pew Report relied on data from the Interior Ministry, which defines Jews according to the Chief Rabbinate’s criteria: individuals born to Jewish mothers or converts recognized by a rabbinical court.

As a result, the survey excluded more than half a million residents who live in Israel under the Law of Return but are classified as having “no religion.”

Majority v. minority

According to DellaPergola, understanding demographic trends within the Jewish community requires recognizing the starkly different realities faced by Jews in Israel versus those living abroad.

“In Israel, Jews are the majority, whereas outside the country, they exist as a small minority,” he explained. “This fundamental difference carries profound psychological, political, financial, and institutional implications — all of which influence demographic patterns.”

Israel also has a higher percentage of religious and ultra-Orthodox individuals, who tend to have a higher birthrate and therefore fuel a more rapid growth.

“However, it is important to consider that the general birthrate in Israel has been stable at around three children per woman for many years,” DellaPergola noted. “This is unique. If we take the 100 most developed countries in the world, not a single state reaches a similar birthrate.”

In light of declining birth rates across much of the Western world, the global Jewish community is entering a new demographic phase, the expert noted.

“For about a century, Jewish diaspora communities generally had lower birthrates than the broader societies in which they lived,” DellaPergola explained. “Today, the trend is shifting, as birthrates in many countries have fallen so low that Jewish families are actually having more children on average.”

This shift is particularly pronounced in communities with larger ultra-Orthodox or religious populations.

“For instance, the Jewish community in the United Kingdom has grown for the first time in decades, largely driven by the Haredi population,” the demographer said.

What about assimilation?

DellaPergola noted that assimilation rates among Jews have recently stabilized after a century.

“For about 100 years, assimilation increased steadily,” he said. “In the US and many European countries, it reached 60%. Essentially, it can’t go higher.”

At the same time, he pointed out a growing trend of assimilated or partially assimilated Jews reconnecting with their Jewish identity. “Much of this resurgence has been driven by external pressures,” he explained. “Whether labeled antisemitism or anti-Zionism, the phenomenon has surged dramatically over the past 15 to 20 years.”

According to DellaPergola, surveys from multiple countries consistently report a rise in antisemitic attitudes in recent years.

“People increasingly perceive hostility, which fuels a need for solidarity and community, a search for friendly faces,” he said.

He added that while the Hamas attacks on Israel on October 7, 2023, and the subsequent conflict are likely influencing these dynamics, it will take years to fully understand their impact on assimilation trends within Diaspora communities.

Should I stay or should I go?

At the same time, DellaPergola emphasized that, for the first time in 40 years, Israel experienced an immigration deficit between 2023 and 2024, with more people leaving the country than immigrating or returning to it.

“It takes about 12 months to see if someone who exited the country did so in some permanent way,” DellaPergola said. “Some 80,000 people who had left Israel by 2023 had not returned yet by December 2024. During the same period, approximately 30,000 Israelis returned to the country from abroad, and another 30,000 immigrated. This still leaves Israel with 20,000 fewer people. It is unprecedented.”

According to DellaPergola, most trends in Aliyah (immigration) and Yeridah (emigration) are closely tied to economic factors.

“Examining unemployment rates and other economic indicators in Israel and abroad often provides a reliable forecast of migration patterns in any given year,” he explained.

“However, in this case, the trend began before October 7 at the time of the judicial overhaul, which was not an economic phenomenon,” DellaPergola added. He was referring to the current government’s controversial attempt in spring 2023 to drastically shift the balance of power between the judiciary and the executive – an effort that sparked mass protests involving hundreds of thousands of people.

According to DellaPergola, Israel’s political trajectory will continue to shape both emigration rates and the decisions of Diaspora Jews facing antisemitism about whether to make Israel their home.

However, within the next decade, the demographer projects that half of the world’s Jewish population will reside in Israel.

“Today, approximately 45% of Jews live in Israel, and that share increases by about half a percentage point each year,” said DellaPergola. “Reaching the 50% mark will be another historic milestone — just like when the global Jewish population will surpass its pre-Holocaust numbers.”