≥ IQ 175 (S.D. 15, Wechsler Scale)
≥ IQ 180 (S.D. 16, Stanford-Binet Scale)
≥ IQ 220 (S.D. 24, Cattell Scale)
≥ IQ 220 (S.D. 24, Mensa Korea Scale)
1. Requirement: Evidence of one standardized IQ test score officially accredited by a professional psychologist (Full documents) at or above IQ Four SD, 1st attempt. (Please see 4. Note.)
2. Requirement: Evidence of one score from a standardized IQ test at or above IQ 180 sd16 at 1st attempt, or Evidence one score of independent high range intelligence test (created by whom having PhD or its equivalent), at or above IQ 180 sd16.
3. Alternative: Evidence Profoundly High Profile at least from one field in real world. (e.g. top-class education attainment; world-class research achievement in each academic field; winner in a major intellectual championship)
4. Alternative: Having one of full memberships from Mega Society, Omega Society or Olympiq Society would qualify to join ESA, only if having one standardized IQ test score of 4 sigma (full scale) or a doctoral degree accredited by a top-class university.
(A full member of Mega International Society automatically qualify for the full membership of Extreme Sigma Associate, ESA Society.)