🌍 How Rare Are You in France?
🇫🇷 Genetic Landscape of France
France bridges Northern and Southern Europe genetically, with a remarkable gradient from the Germanic north to the Mediterranean south. Brittany carries Celtic genetics similar to Ireland and Wales. Basque Country in the southwest holds one of Europe's most ancient and genetically distinct populations with the world's highest Rh-negative rate (~35%). Alsace shows Germanic influence, while Provence reflects Italian and Mediterranean heritage. France's colonial history means significant North African, West African, and Caribbean genetic contributions in major cities. The country has one of Europe's most balanced eye color distributions.
Until 1993, parents could not simply choose a first name. A Napoleonic-era law limited registrars to names drawn from the calendar of saints and from figures of ancient history, and officials used it to refuse Breton and Occitan spellings well into the twentieth century. The rule is gone, but its habits remain: French given names move in strong generational waves, so a name often gives away roughly when its owner was born. Rarity is also unusually hard to measure here, because the state collects no official statistics on ethnic or racial origin — country of birth is recorded, ancestry is not. That is a deliberate republican principle rather than an oversight, and it means questions other countries answer with a census table have no official answer in France.
✍️ The Marks a French Register Will Write
A Justice Ministry circular of 23 July 2014 sets out which diacritics a French civil-status record may carry: points, trémas, accents and cedillas. The tilde is not one of them. Quimper registered a child as Fañch in May 2017; that September the tribunal de grande instance de Quimper refused to homologate the name, citing the circular. The cour d'appel de Rennes reversed on 19 November 2018, and the Cour de cassation confirmed that ruling on 17 October 2019 without deciding the tilde question itself.
Parliament then wrote regional-language diacritics into law. On 21 May 2021 the Conseil constitutionnel struck that article down: allowing marks not used in writing French would recognise a right to use a language other than French with public services, against article 2 of the Constitution. A 2024 ministerial answer says amending the 2014 circular is therefore not legally possible. Whether two people share a name can come down to one mark the register will not write.
👁️ Eye Color
| Brown | 34% |
| Blue | 22% |
| Green | 20% |
| Hazel | 16% |
| Gray | 8% |
💇 Hair Color
| Brown | 40% |
| Dark Brown | 20% |
| Black | 18% |
| Blonde | 15% |
| Red | 2% |
| Other | 5% |
🩸 Blood Type
| O+ | 36% |
| A+ | 34% |
| B+ | 9% |
| O- | 7% |
| A- | 7% |
| AB+ | 4% |
| B- | 2% |
| AB- | 1% |
Trait frequencies on this page come from public and institutional datasets — see Data Sources.
🧮 Calculate Your Rarity in France
Pick your eye colour, hair colour and blood type. The calculator uses France's own figures from the tables above, not world averages.
This is an estimate, not a measurement. It multiplies three national frequencies as if they were independent, and they are not: eye and hair colour share pigmentation genes, so a combination that tends to run together, such as blue eyes with blonde hair, is more common than the multiplication suggests, while one that rarely does, such as blue eyes with black hair, is rarer. Blood type is independent of both. The frequencies are national averages from public datasets — see Data Sources.
That number describes the body you were born with. Fraeon, our other site, does the same arithmetic for the part you chose: the films, series, games, books, anime and manga you have actually finished. Start your log →
👶 Who Decides the Surname, and What Parents Picked in 2025
The loi n° 2002-304 of 4 March 2002 rewrote article 311-21 of the Code civil: parents declaring a birth may give the child the father's name, the mother's name, or both joined in the order they choose, one name from each. Absent a joint declaration, what happens depends on how filiation was established: where the parents are married or the father recognised the child first or at the same time, the child takes the father's name; where both recognised at once and the parents disagree, the child takes both names in alphabetical order; where only the mother's filiation is established, the child takes hers. The name chosen for the first child applies to all the couple's common children. The rules apply to children born from 1 January 2005, the date set by the law of 18 June 2003 on the dévolution of the family name.
Insee has measured what parents do with the choice. Of the 644,000 children born in France in 2025, 77.9% got only the father's name, 15.1% both names and 6.8% only the mother's. Double names were 10.3% in 2014, so the share rose 4.8 points in eleven years. Unmarried parents picked a double name nearly three times as often as married parents, 22% against 8%.
🗓️ The Years When French Birth Dates Were Not Gregorian
The secular état civil is a few months older than the calendar its early entries are written in. The law of 20–25 September 1792 secularised the état civil from 1 January 1793 and put the registers in the hands of the mayor. In October 1793 the Convention created a new calendar for the Republic, backdated to the proclamation of the Republic on 22 September 1792, its months named after weather and harvest: vendémiaire, brumaire, frimaire, nivôse. An imperial decree of 9 September 1805 ended it, and the Gregorian calendar resumed on 1 January 1806.
So for a stretch of French births between 1793 and 1805, the date the state wrote down is not a Gregorian date. Departmental archives treat this as routine: the Finistère archives note that their état civil search form carries a Republican-calendar date converter. A birth date is a record kept in whichever calendar the administration was using at the time — our birthday page counts in Gregorian ones.
⭐ Rare Facts About France
Where the France figures come from
Population is Insee, Bilan démographique 2025: 69.1 million residents at 1 January 2026. Blood groups should be read against the Établissement français du sang's own shares, which put A+ at 38% and O+ at 36%. Adult height is measured by Santé publique France in the Esteban study, 2014–2016. The eye and hair colour figures are estimates from non-official sources, not institutional statistics: Insee's national identification register records only name, first names, sex, and the date and place of birth and death. Last checked September 2026. See Data Sources.