How Many Orthodox Jews Are There?

People are often surprised by the numbers. If you are new here, the foundations of Orthodox Judaism are worth reading first — it will make the community picture below easier to follow. Orthodox Jews are visible — our distinctive dress, our concentrated neighborhoods, our large families — but we are actually a relatively small percentage of the total Jewish population. What is less obvious from the statistics is the trajectory: we are the fastest-growing Jewish community in the world, and the demographics are shifting rapidly.

The Numbers

The total Jewish population worldwide is around 15.7 million (per demographer Sergio DellaPergola's figures in the American Jewish Year Book). Of those, somewhere in the neighborhood of 3.5 to 4 million are Orthodox — roughly a fifth to a quarter of world Jewry, depending on how you draw the boundaries. The bulk of us are in just two places.

Israel: About 2 million, including roughly 1.4 million Charedi (ultra-Orthodox, about 14% of Israel's population per the Israel Democracy Institute's 2024 statistical report) and roughly 700,000 Dati Leumi (national religious/Modern Orthodox). This is the engine of the whole picture — Israel's Charedi population alone is growing faster than almost any group in the developed world. Jerusalem and Bnei Brak are the centers, with dozens of other cities besides.

United States: About 800,000 Orthodox Jews (Pew Research Center, 2020), heavily concentrated in the New York metro area — Brooklyn (Boro Park, Williamsburg, Crown Heights, Flatbush), Lakewood NJ, Monsey NY, the Five Towns, and Teaneck NJ. Significant communities also sit in Baltimore, Chicago, Los Angeles, Miami, Detroit, and Cleveland.

United Kingdom (~75,000): Centered in Stamford Hill (London), Manchester, and Gateshead.

Everywhere else: Canada (Toronto, Montreal), France (Paris), Belgium (Antwerp), Switzerland (Zurich), Australia (Melbourne), South Africa (Johannesburg), and South America (Buenos Aires, Sao Paulo) all have communities you would recognize the moment you walked in.

I will be honest about why these numbers wobble depending on the source: "Orthodox" is partly self-definition and partly observable practice, and the diaspora counts in particular are estimates, not a census. But the rough shape — Israel first, the US a distant second, everyone else trailing — is solid.

Why It's Growing

Here is the number that gets demographers' attention. Hasidic and Yeshivish families often have six to ten children, with families of ten or more not uncommon in Hasidic communities; Modern Orthodox families typically have three to five. Compare that to American Jewry as a whole, where Pew puts completed fertility at roughly 1.9 children per Jewish woman. On my own block in Boro Park there are more children than on the entire suburban street where one of my non-Jewish friends grew up, and that gap is not an accident — it is arithmetic, repeated generation after generation.

Birth rates are only half of it. Retention is the other half, and this is where the story has genuinely shifted. Yes, some young people leave (the "OTD" — off the derech — phenomenon is real, and every family knows someone). But Pew's data shows retention rising sharply by generation: older Orthodox-raised Jews left at high rates, while among younger cohorts the share who stay Orthodox now runs well above 80%, and higher still in Hasidic and Yeshivish communities. Fewer leaving, while each family raises many — that is what compounds.

The result shows up clearly in the American numbers. Pew's 2020 survey found Orthodox Jews at about 10% of American Jewry overall, but a much larger share of the youngest Jews — only a small fraction of Jews over 65 are Orthodox, versus a far larger fraction of those under 18. Meanwhile Conservative and Reform affiliation has been shrinking. Demographers project that Orthodox Jews could be a quarter or more of American Jewry by mid-century, and the majority of religiously engaged American Jews by the latter half of it.

Why It Matters

This is not just a statistical curiosity — it is reshaping American and world Judaism on the ground. Orthodox communities are building new schools, synagogues, and mikvaot at a steady clip. Lakewood, New Jersey — home to Beth Medrash Govoha, the largest yeshiva in North America — has grown from a modest community into a city of over 135,000, driven largely by Orthodox families.

The growth brings real challenges too: housing prices, school capacity, local politics, and the economic infrastructure it takes to support large families. These are not abstractions; they are the kitchen-table conversations of the communities living through it.

A Small Community with an Outsized Presence

Orthodox Jews are a small slice of world Jewry, but the community's footprint is enormous — in Torah scholarship, in Jewish education, in charitable giving, in the sheer density of Jewish life. Walk through any Orthodox neighborhood on a Friday afternoon and you will feel it: the rush of preparation, the smell of challah baking, the energy of a community that is very much alive and growing.

We are small. But we are not going anywhere. If anything, we are just getting started.

If you are curious why the families are so large in the first place, here is the fuller story.

Common Questions

What percentage of Jews worldwide are Orthodox? Roughly a fifth to a quarter of the global Jewish population — about 3.5 to 4 million of some 15.7 million Jews. Among those who actively practice Judaism, the proportion is far higher, and rising.

Are all Hasidic Jews counted as Orthodox? Yes — Hasidic Jews are a subset of Orthodox Judaism. All population counts of Orthodox Jews include Hasidic, Yeshivish, and Modern Orthodox communities.

Is the Orthodox community growing or shrinking? Growing — significantly. With six-plus children per family in much of the community and strong retention, the Orthodox population roughly doubles within a generation. This is the opposite of the trend in most Western religious communities.

Why do Orthodox Jews have so many children? Multiple reasons: religious value placed on children, the commandment to "be fruitful and multiply," community support systems that make large families viable, and a cultural framework that sees children as the highest blessing. Read more about why Orthodox families are large.