The Janssen surname
In the 2000 U.S. Census, 10,720 people carried this name — #3,100 among all U.S. surnames, about 1 in every 25,200 people counted.
In Belgium’s population register
At least 9,023 people named Janssen live in Belgium.
Statbel only publishes a name in a municipality when five or more people there share it, so the real number is higher. Most of them live in Limburg.
Where it concentrates, on the mapWhere they live today
Statbel (Statistics Belgium), family names of the population by municipality, 1 January 2026 — CC BY 4.0.
In France’s civil register
France’s register of deaths holds 449 people named Janssen.
84 of them were born outside France. Those born in France came from 33 départements, most often Nord.
Where it concentrates, on the mapWhere they were born
Fichier des personnes décédées, INSEE — Licence Ouverte 2.0 · deaths recorded in France since 1970, by place of birth.
In Switzerland’s population statistics
372 people named Janssen live in Switzerland.
They live in 19 of Switzerland’s 26 cantons, most of all in Zurich.
Where it concentrates, on the mapWhere they live today
Swiss Federal Statistical Office (FSO), «Surnames of the permanent resident population by canton», 2025, opendata.swiss · names with fewer than 3 bearers in a canton are not published.
In Poland’s population register
48 people named Janssen have a registered home in Poland.
Of the 166 in Poland’s national register, these are the ones with a permanent address on file. They live in 9 of Poland’s 16 voivodeships, most of all in Lower Silesian.
Too few records to say where it concentrates region by region — these are plain counts, not shares.
Where they live today
PESEL register, Ministry of Digital Affairs of Poland (dane.gov.pl) — CC0 · living people by voivodeship of permanent residence, 20 January 2026.
In print
Janssen in American newspapers,
1907–1963.
Chronicling America, Library of Congress — digitised newspapers in the public domain · 26,774 pages in all carry the name.
Who carried it
People named Janssen,
with a public archive behind them.
-
Zaccarias Janssen 1580–1630 · mechanic -
Jacob Janssen 1742–1813 · politician -
Carl Janssen 1813–1884 · priest -
Pierre Janssen 1824–1907 · astronomer -
Johannes Janssen 1829–1891 · writer
Wikidata and Wikimedia Commons (CC0) · 190 lives in all are documented under this name.
Nearby in the index
Surnames next to Janssen.
- Jannetta 149 · U.S. census
- Janny 130 · U.S. census
- Janowski 2,020 · U.S. census
- Jans 1,096 · U.S. census
- Jansen 16,036 · U.S. census
- Janson 3,865 · U.S. census
- Janssens 522 · U.S. census
- Janton 133 · U.S. census
- Jantzen 1,557 · U.S. census
- Janus 2,118 · U.S. census
- Janusz 1,115 · U.S. census
- Janvier 961 · U.S. census
When the index is not enough
This page says where Janssen is.
A volume says what happened to it.
Every page in the index is free and stays free. The Heritage Volume is the long form: the full paper trail, the arms, the crossing — bound, and yours.