Mensa is the world's oldest and largest high-IQ society, welcoming individuals who score in the top 2% of the population on a standardized intelligence test. This comprehensive guide covers the history of Mensa, membership requirements, Riverside's connection to Mensa, and everything you need to know about testing in Riverside.

Last Updated: August 2026

The History of Mensa

The Founding: Oxford, England (1946)

Mensa was founded in England in 1946 by Roland Berrill and Dr. Lancelot Ware. The name comes from the Latin word for “table,” reflecting the concept of members meeting as equals. Membership is based on qualifying performance on an accepted standardized intelligence test.

The Early Years

The organization expanded internationally and developed national groups, local chapters, publications, scholarship programs, gifted-youth resources, special-interest groups, and social events. American Mensa is the U.S. national organization.

Mensa's Three Purposes

• Identify and foster human intelligence for the benefit of humanity.
• Encourage research into the nature, characteristics, and uses of intelligence.
• Provide an intellectual and social environment for members.

Riverside's Connection to Mensa

Riverside-area residents may be assigned to Orange County Mensa or San Diego Mensa depending on ZIP code and American Mensa's current chapter boundaries. Orange County Mensa states that its territory includes part of Riverside along the SR-91 corridor, while San Diego Mensa reports that it serves most of Riverside County. Members may attend regional social, discussion, game, scholarship, gifted-youth, and testing activities depending on current volunteer schedules.

The city's universities, healthcare systems, Inland Empire logistics economy, multilingual professional community, public agencies, and technology and education programs provide a natural base for people interested in Mensa. Official eligibility, testing dates, prior-evidence rules, chapter assignment, and local events should always be confirmed through American Mensa and the current regional group websites.

Mensa Qualifying Scores

To qualify for Mensa, you must score at or above the 98th percentile on an approved standardized intelligence test. This means performing better than 98 out of every 100 people who take the same test.

Qualifying Scores by Test

Note that different tests use different standard deviations, which is why the qualifying scores vary. The consistent requirement is the 98th percentile.

Mensa in Riverside

Regional Mensa Coverage

• Chapter boundaries: Riverside-area residents may fall within Orange County Mensa or San Diego Mensa depending on ZIP code and American Mensa's current assignments.
• Orange County Mensa: Its official area description includes part of Riverside along the SR-91 corridor.
• San Diego Mensa: Its published territory includes most of Riverside County.
• Membership count: No authoritative Riverside-only membership total is published; chapter counts and boundaries can change.
• Current verification: Use American Mensa's chapter directory and the local groups' official sites for assignment, testing, and events.

Who Takes the Mensa Test in Riverside?

• Adults seeking membership: Professionals, students, retirees, career changers, and people interested in high-IQ community activities.
• Prior-evidence applicants: Individuals who already have qualifying scores from an accepted standardized test.
• Parents of gifted youth: Families exploring Mensa resources after appropriate professional or school testing.
• University students: UCR, CBU, La Sierra, RCC, Loma Linda, Cal State San Bernardino, and other students may explore membership.
• Important distinction: The Mensa Admission Test establishes eligibility only and is not a clinical IQ evaluation or diagnostic report.

Riverside-Area Mensa Events

• Local gatherings: Social, discussion, game, dining, speaker, and special-interest activities depend on volunteer schedules.
• Testing sessions: Availability depends on authorized proctors and current American Mensa procedures.
• Travel: Events or testing may require travel toward Orange County, Corona, Temecula, San Diego County, or other chapter locations.
• Gifted youth: Programs may be coordinated by chapter volunteers and should be confirmed directly.
• Scholarships: American Mensa and local groups may participate in annual scholarship programs under current rules.
• Regional and national events: Members may attend broader gatherings and special-interest activities beyond the local area.
• Current information: Confirm dates, costs, age restrictions, registration, and accessibility through official Mensa channels.
• Volunteer structure: Event frequency depends on member volunteers, venue access, and regional travel distances.

Accepted Tests for Mensa Qualification

American Mensa accepts scores from approximately 200 different standardized intelligence tests. Tests must be administered by a neutral and qualified third party in a traditional testing environment.

Tests Commonly Administered by Psychologists

• Wechsler Adult Intelligence Scale (WAIS) – FSIQ 130
• Wechsler Intelligence Scale for Children (WISC) – FSIQ 130
• Stanford-Binet Intelligence Scales – IQ 130-132 (depending on version)
• Reynolds Intellectual Assessment Scales – IQ 130
• Differential Ability Scales (DAS) – GCA 130-132

Tests Administered by Schools

• Cognitive Abilities Test (CogAT) – Composite SAS 132
• Otis-Lennon School Ability Test (OLSAT) – Total SAI 132
• Naglieri Nonverbal Ability Test (NNAT) – Nonverbal Ability Index Score 130-132
• Woodcock-Johnson Test of Cognitive Abilities – IQ 131-132

College Preparatory Tests

• SAT (pre-1994) – Combined Verbal & Math 1250+
• GRE (pre-2001) – Combined Verbal & Quantitative 1250+
• ACT (pre-September 1989) – Composite 29+

The Mensa Testing Process

Two Ways to Qualify

There are two primary pathways to Mensa membership:

1. Take the Mensa Admission Test: A supervised test administered by Mensa proctors
2. Submit prior evidence: If you've already taken an approved test and scored at the 98th percentile, you can submit those scores

The Mensa Admission Test

The Mensa Admission Test is administered in supervised sessions held in cities nationwide, including Riverside. Key details:

• Duration: 1-2 hours total
• Format: Two separate timed tests (the Wonderlic and Culture Fair tests)
• Qualifying: You only need to qualify on one of the two tests
• Cost: Approximately $40 for the test
• Retake policy: You can retake the test once every eight weeks

What the Mensa Admission Test Measures

• Pattern recognition – Identifying sequences and relationships
• Logical reasoning – Deductive and inductive thinking
• Spatial visualization – Mental manipulation of objects
• Problem-solving – Complex reasoning under time pressure

Important: The Test is for Admission Only

The Mensa Admission Test is specifically designed for admission to Mensa and does not provide a detailed IQ score or report. You will only be notified whether you qualified for membership. If you want a detailed IQ report with index scores, you should take a professionally administered test like WAIS-IV or SB-5 with a licensed psychologist.

Frequently Asked Questions