Is 128 a Good IQ Score?

What an IQ of 128 means, where it ranks, and what it tells you about cognitive ability.

128

IQ Score

97th

Percentile

Superior

Classification

1 in 32

Rarity

What an IQ of 128 means

An IQ of 128 sits at the 97th percentile, in the top 3% of the population. Roughly 1 in 33 people score 128 or above. This is well into the range where people consistently outperform peers in complex analytical, technical, and leadership roles. The Mensa threshold sits at IQ 130, which is 2 points above your score.

IQ 128 in context

IQ 128 sits 13 points above the one-standard-deviation mark of 115 and 2 points below the Mensa threshold at IQ 130. At the 97th percentile, roughly 1 in 33 people score here or above. Research on occupational outcomes places IQ 128 solidly in the range where graduate-level academic tracks and demanding analytical careers are cognitively accessible without exceptional effort. Studies of professional performance note that in this range, cognitive ability and conscientiousness interact most productively — the combination consistently outperforms either factor alone. IQ 128 is 28 points above the population mean, a gap that becomes most visible in tasks involving novel problem-solving under time pressure.

Frequently asked questions

Is 128 a good IQ score?

Yes. An IQ of 128 is well into the Superior range at the 97th percentile. About 1 in 33 people score 128 or above. This sits 2 points below the Mensa threshold of 130 — well within the same cognitive territory.

What percentile is an IQ of 128?

The 97th percentile. That means 97% of the population scores at or below 128. Roughly 1 in 33 people score 128 or above. The population mean is 100 with a standard deviation of 15.

What careers are associated with an IQ of 128?

Most elite professional fields are accessible here. Medicine, law, research, and senior leadership roles all cluster in the Superior range. IQ 128 sits 2 points below the Mensa threshold but well within the same cognitive band as many leading academics and executives.

Can you improve an IQ of 128?

Scores in the Superior range are strongly shaped by genetics. That does not mean fixed. Sleep quality, working memory training, and nutrition all have documented effects on fluid intelligence. The realistic expectation is a few points — not large jumps.

Careers that commonly score in this range

Physician / DoctorMean ~120–125 in multiple studies

Attorney / BarristerLaw school graduate mean ~115–122

Chartered AccountantComplex financial reasoning correlates with this range

Senior EngineerStructural, electrical, and aerospace engineering roles

Notable people reportedly in this range

All figures are estimates or reported by third-party sources — none are clinically verified.

George W. Bush

43rd US President — Yale and Harvard Business School graduate. Analysis of his 1206 SAT score (1964 scale) using the Frey-Detterman correlation estimates his IQ at approximately 120–125.

Oprah Winfrey

Media executive, actress, and philanthropist — Tennessee State University graduate and one of the most successful self-made entrepreneurs in US history. Published profiles estimate her IQ at approximately 115–120, with particular strength in emotional and interpersonal intelligence.

J.K. Rowling

Author of the Harry Potter series — University of Exeter graduate in French and Classics. Published assessments estimate her IQ at approximately 128–136, consistent with the internal consistency and narrative complexity of a seven-volume fictional universe.

Colin Powell

Former US Secretary of State and Chairman of the Joint Chiefs — CCNY graduate and career military officer. IQ widely cited at approximately 127–132 in published assessments of senior military and political leadership cognitive profiles.

From the IQScore blog

Further reading selected for this score range.

Fluid vs Crystallised Intelligence →

The two cognitive systems driving your score profile.

Average IQ by Profession →

Where scores in this range cluster across careers.

How Much of IQ Is Genetic? →

What twin studies say about scores in the superior range.

Working Memory and Intelligence →

The component most closely tied to fluid IQ, and the most trainable.