Mensa by the numbers

01 Key findings

1. Mensa’s own websites disagree on its size. Mensa International’s About page says “around 170,000” in its header and “around 150,000” in its text; 33 statements on 26 Mensa websites range from 100,000 to 170,000.Mensa websites, read 15 October 2026; IQ Metrics Research
2. The national counts add up to about 143,000. That is the sum of the 27 national Mensas that publish a figure, closer to the 150,000 than to the 170,000.Mensa websites, read 15 October 2026; IQ Metrics Research
3. Sweden has the most members per person. About 755 per million people, then Singapore (654) and Finland (620). Mensa India has about 1 per million.Mensa websites, read 15 October 2026; IQ Metrics Research; World Bank population
4. American Mensa is the largest. It says it has “more than 40,000” members; Mensa International’s pages say around 42,000 and “nearly 50,000”.Mensa websites, read 15 October 2026; IQ Metrics Research
5. 39 children joined in the news in two years. The median age was 7, 8 were under 5, and boys outnumbered girls 21 to 10 where the story said.Google News (US and UK editions), Oct 2024 to Sep 2026; IQ Metrics Research

02 Statistics to quote

03 How many members does Mensa have?

Mensa International’s About page has grown its figure over time: from “around 110,000” in 2010 to “around 150,000” from 2024 ^[4]. In September 2026 the header of the page changed to “around 170,000”, while the text below it still says “around 150,000” ^[1].

Figure 1

Worldwide membership stated on Mensa International's About page

Thousands of members. First archived copy of each year; 2020 to 2023 have no archived copy of this page.

2010110k

2011110k

2012110k

2013110k

2014110k

2015120k

2016120k

2017134k

2018134k

2019134k

2024150k

Jan 2026150k

Oct 2026 (header)170k

The national Mensas repeat different totals. We found 33 statements of the worldwide total on 26 Mensa websites. They range from 100,000 to 170,000; 150,000 is the most common.

Figure 2

Worldwide totals stated on Mensa websites

Number of statements giving each total. 33 statements on 26 websites, read 15 October 2026.

100,0003

110,0001

120,0001

128,0001

134,0001

140,0005

146,0001

150,00013

153,0001

160,0001

161,0001

170,0004

Table 1

Every statement of the worldwide total

As written on each site, in its own language. Click a column heading to sort.

Website	Total	What it says
Mensa France	170,000	170 000 Membres internationaux
Mensa HungarIQa	170,000	Mensa-tagok száma a világon 170000
Mensa International (mensa.org)	170,000	The High IQ Society with around 170,000 members of all ages in 90+ countries worldwide
Mensa Spain	170,000	Mensa cuenta con más de 170.000 miembros
Mensa Poland	161,000	161000 członków na Świecie
Mensa Norway	160,000	Internasjonalt er det over 160 000 medlemmer av Mensa
Mensa Germany	153,000	Insgesamt hat Mensa aktuell über 153.000 Mitglieder
Australian Mensa	150,000	with well over 150,000 members
Japan Mensa	150,000	会員数は全世界100ヶ国以上で15万人以上
Mensa Belgium	150,000	with more than 150 000 members worldwide
Mensa Brazil	150,000	No mundo todo, a Mensa alcançou 150 mil membros
Mensa Croatia	150,000	Mensa ima više od 150.000 članova
Mensa Czech Republic	150,000	150 000 Celkový počet členů Mensy ve více než 100 zemích
Mensa Denmark	150,000	Foreningen tæller ca. 150.000 medlemmer på verdensplan
Mensa Finland	150,000	jossa on maailmanlaajuisesti n. 150 000 jäsentä
Mensa Hong Kong	150,000	Currently, there are approximately 150,000 members in around 50 countries worldwide
Mensa International (mensa.org)	150,000	The worldwide membership of Mensa currently stands at around 150,000
Mensa Italy	150,000	Ad oggi il Mensa vanta oltre 150.000 soci
Mensa Norway	150,000	og over 150 000 medlemmer på verdensbasis
Mensa Romania	150,000	cu aproximativ 150.000 de membrii
Mensa Poland	146,000	Mensa zrzesza blisko 146 tysięcy członków
American Mensa	140,000	There are currently more than 140,000 members worldwide
Australian Mensa	140,000	with over 140,000 members in 47 national organisations
British Mensa	140,000	140000 (People, “Around the world”)
Mensa HungarIQa	140,000	Ma közel 140 ezer tagja van a világ száz országában
Mensa Sweden	140,000	I hela världen finns det över 140 000 personer som är medlemmar i Mensa
Mensa Bulgaria	134,000	Днес те са около 134000 в 100 страни по света
Mensa Slovenia	128,000	Mensa ima širom sveta več kot 128 000 članov
Mensa Spain	120,000	Mensa tiene más de 120.000 socios en todo el mundo
Mensa Mexico	110,000	que comprende a más de 110 mil miembros en 100 países
Japan Mensa	100,000	世界100ヶ国以上、10万人以上の会員を持つ
Mensa Netherlands	100,000	met ruim 100.000 leden
Mensa New Zealand	100,000	Today there are over 100,000 Mensans in 100 countries throughout the world

04 Which countries have the most Mensa members?

27 national Mensas publish a member count, on their own website or on their page at Mensa International. Where both exist they often differ: Mensa Germany says “more than 20,000”, its Mensa International page “around 17,700”; Japan Mensa says more than 7,000, its page around 5,900. We use each group’s own figure where it has one. Added up, the 27 counts come to about 143,000.

Figure 3

Mensa members per million people

Each national Mensa's published member count divided by the population (World Bank, 2025). British Mensa covers the UK and Ireland.

Sweden755

Singapore654

Finland620

Czechia588

Hungary581

Norway535

Montenegro465

Croatia373

Denmark350

Germany240

United Kingdom and Ireland227

Slovenia141

United States117

Australia116

Greece115

Hong Kong80

Poland74

Spain71

France66

Japan57

Italy42

Romania32

Malaysia22

Argentina11

Brazil10

Mexico3

India1

Figure 4

The ten largest national Mensas

Members, as each group states it ("more than", "around").

American Mensa40,000

Mensa Germany20,000

British Mensa17,000

Mensa Sweden8,000

Japan Mensa7,000

Mensa Czech Republic6,400

Mensa HungarIQa5,529

Mensa France4,565

Mensa Singapore4,000

Mensa Finland3,500

Table 2

Every national Mensa that publishes a count

Own website = the national Mensa's site; Mensa International = its page on mensa.org. Rank = members per million people. Mensa Netherlands is not ranked: its only figure is from 2014.

National Mensa	Own website	Mensa International	Per million	Rank
American Mensa	more than 40,000	around 42,000	117	13
Mensa Germany	more than 20,000	around 17,700	240	10
British Mensa (UK and Ireland)	around 17,000	more than 17,000	227	11
Mensa Sweden	over 8,000	–	755	1
Japan Mensa	more than 7,000 (end of March 2025)	around 5,900	57	20
Mensa Czech Republic	6,400	–	588	4
Mensa HungarIQa (Hungary)	5,529	–	581	5
Mensa France	4,565	around 4,700	66	19
Mensa Singapore	–	around 4,000	654	2
Mensa Finland	over 3,500	–	620	3
Mensa Spain	more than 3,500 (January 2026)	–	71	18
Australian Mensa	3,200 (2026)	around 3,143	116	14
Mensa Norway	around 3,000 (end of 2025)	around 2,600	535	6
Mensa Poland	2,700	–	74	17
Mensa Italy	over 2,500	around 2,600	42	21
Mensa Brazil	–	around 2,200	10	25
Mensa Denmark	over 2,100	–	350	9
Mensa India	–	around 2,000	1	27
Mensa Croatia	1,445 (end of 2025)	around 1,200	373	8
Mensa Greece	over 1,200 active	around 1,260	115	15
Malaysian Mensa	–	around 800	22	23
Mensa Hong Kong	more than 600	around 630	80	16
Mensa Romania	–	around 600	32	22
Mensa Argentina	–	around 520	11	24
Mensa Mexico	–	around 400	3	26
Mensa Slovenia	almost 300	around 400	141	12
Mensa Montenegro	–	around 290	465	7
Mensa Netherlands	just over 4,500 (end of 2014)	–	–	–

05 Your country's Mensa, in one sentence

Pick a country to see its national Mensa’s size, its share of the population and its rank. Every country has its own link and a card you can download or share.

06 How many children are in Mensa?

Mensa International describes its members as being “of all ages” ^[1]. Some national Mensas say how many are children: 1,800 of Mensa Czech Republic’s 6,400 members belong to its Children’s Mensa ^[5], and Australian Mensa says over 40% of its members are under 18 ^[6]. The national Mensas’ own tests are for older candidates: 14 and over at American Mensa ^[8], over ten and a half at British Mensa ^[7]. Younger children join with an accepted result from a psychologist’s test. The youngest members on record joined at two: a boy in the UK at 2 years 182 days ^[10] and a girl in the US at 2 years 195 days ^[11].

Local news covers children joining Mensa almost every month. We read every story about Mensa in Google News (US and UK editions) from October 2024 to September 2026: 105 stories reported 39 children joining, about 1.6 a month ^[13]. Several stories about the same child count as one child.

Figure 5

Children reported joining Mensa, by quarter

Each child counted once, in the quarter of the first story. English-language Google News, US and UK editions.

Q4 20242

Q1 20255

Q2 20256

Q3 20254

Q4 20254

Q1 20262

Q2 20269

Q3 20267

Figure 6

Age of the children when the news reported them

36 children whose age the story gave. Median age 7; youngest 2, oldest 13.

Age 2-48

Age 5-712

Age 8-1010

Age 11-136

07 How do you qualify for Mensa?

Mensa takes anyone who scores at or above the 98th percentile, the top 2%, on an approved intelligence test. Tests use different scales, so “a result on one test of 132 can be the same as a score of 148 on another test” ^[3]. In Sweden the minimum is 130 on the Wechsler scale ^[9]. For the exact score each accepted test needs, see our guides Mensa IQ requirement and Mensa IQ score requirements, and high-IQ societies explained.

08 How we built this

1. 01

   Mensa's own pages

   We saved the About page of Mensa International, its pages for 20 national groups, and the websites of 29 national Mensas on 15 October 2026, 74 pages in all with the Guinness World Records pages. Every figure on this page is checked by a script against the saved text.

2. 02

   Members by country

   We used the national Mensa’s own figure where it publishes one, otherwise its Mensa International page. Figures are kept as stated (“more than”, “around”); we did not adjust them. Per-million figures use World Bank population for 2025 ^[12].

3. 03

   The worldwide total over time

   The first archived copy of each year of mensa.org/about-us/ in the Wayback Machine, 2010 to 2026 ^[4].

4. 04

   Children in the news

   Google News searches for Mensa stories, month by month, in the US and UK English editions ^[13]. We read each story, kept the ones about a child newly accepted or qualifying, and counted each child once. We do not publish children’s names: our tables keep only the age, country and gender a story gives, and any IQ score it prints.