The smartest person in the world, by documented achievement, is the mathematician Terence Tao, and our list of ten runs from the Fields Medal winners to a Nobel-winning AI researcher. Nobody can crown a single smartest human, because the famous IQ numbers online come from unsupervised tests and a retired record category, so we rank by what each person demonstrably did.
The first edition of this article, from 2016, leaned on claimed IQ scores of 190 to 230. We dropped the ones we could not stand behind and replaced them with people whose results are on the public record: medals, proofs, prizes and wins.
| Rank | Name | Proof of brilliance |
|---|---|---|
| 1 | Terence Tao | Fields Medal 2006, Breakthrough Prize 2014 |
| 2 | Edward Witten | Fields Medal 1990, the first physicist to win one |
| 3 | Grigori Perelman | Proved the Poincare conjecture, declined the Fields Medal and the $1 million prize |
| 4 | Andrew Wiles | Proved Fermat’s Last Theorem, Abel Prize 2016 |
| 5 | Peter Scholze | Fields Medal 2018, professor at 24 |
| 6 | Demis Hassabis | Nobel Prize in Chemistry 2024 |
| 7 | Manjul Bhargava | Fields Medal 2014 |
| 8 | Garry Kasparov | World Chess Champion 1985 to 2000 |
| 9 | Kim Ung-yong | Reported IQ above 210 as a child |
| 10 | Marilyn vos Savant | Highest recorded IQ in a retired Guinness category |
The order is our judgement. It weighs the size of the result, how hard it was and how long it has stood, and it is deliberately weighted toward fields where a result can be checked.
1. Terence Tao
Tao skipped five grades in primary school, started at high school at 7 and was taking university maths at 9. He is one of only three children in the history of the Johns Hopkins talent program to score 700 or higher on the SAT math section.
His 2006 Fields Medal came for work spanning partial differential equations, combinatorics, harmonic analysis and additive number theory, and shared the 2014 Breakthrough Prize in Mathematics. The Green-Tao theorem, proved with Ben Green, shows that the prime numbers contain arbitrarily long arithmetic progressions. Tao teaches at UCLA, and has been called the finest mathematician of his generation. That is why he sits first: breadth plus depth, with a record you can look up.
2. Edward Witten
Witten was not a physicist by plan. He took a history degree at Brandeis, wrote for political magazines, worked on a presidential campaign and tried economics for one semester before enrolling in applied maths at Princeton in 1973 and finishing a physics PhD in 1976.
In 1990 he became the first physicist to win a Fields Medal, for mathematical insights such as his 1981 proof of the positive energy theorem in general relativity. Many regard him as the practical founder of M-theory and is professor emeritus at the Institute for Advanced Study.
3. Grigori Perelman
Perelman proved the Poincare conjecture, a problem open for a century, in papers from 2002 and 2003 that developed new techniques for Ricci flow. Science magazine named it the 2006 Breakthrough of the Year.
Perelman then turned down the Fields Medal in 2006 and the Clay Millennium Prize, worth $1 million, in 2010, and lives in seclusion in Saint Petersburg. A person who solves a century-old problem and says no to the money makes the list on achievement and character both.
4. Andrew Wiles
Wiles caught the Fermat bug as a child in Nigeria and later set out to prove it from Princeton. A flaw was found in his 1993 proof, and on 19 September 1994 he and his student Richard Taylor found a way around it. The proof appeared in 1995.
He won the 2016 Abel Prize, was knighted in 2000 and became the first Regius Professor of Mathematics at Oxford in 2018.
5. Peter Scholze
Scholze took three gold medals and a silver at the International Mathematical Olympiad, finished a bachelor’s and master’s in five semesters at Bonn and completed his PhD in 2012. He became a full professor at 24, the youngest in Germany.
His thesis on perfectoid spaces led to a Fields Medal in 2018. He has directed a Max Planck Institute since 2018, and he is a member of an AI-free caucus of mathematicians.
6. Demis Hassabis
Hassabis learned chess at four, rated about 2300 by 13 and finished his A-levels two years early at 16. He started his career writing video game AI and later co-founded DeepMind.
His AlphaFold work on protein structure prediction earned him a share of the 2024 Nobel Prize in Chemistry with John Jumper, and a knighthood the same year. Time named him among its 2025 Architects of AI.
7. Manjul Bhargava
Bhargava completed his high school maths and computer science by 14, graduated Harvard in 1996 and went on to Princeton. His 2014 win came for methods in the geometry of numbers that bound the average rank of elliptic curves.
Bhargava teaches at Princeton and, from February 2026, the first president of the National Museum of Mathematics in New York.
8. Garry Kasparov
Kasparov became the youngest undisputed world champion at 22 in 1985, beating Anatoly Karpov, a record that stood until 2024. He was world number one for 255 months and reached a rating of 2851 in 1999.
In 1997 he lost a match to IBM’s Deep Blue, the first world champion to lose to a computer under standard time controls. The original version of this article said he drew a computer in 2013, which does not match the record, and we removed it.
9. Kim Ung-yong
Kim is a South Korean civil engineer and professor who is best known as a child prodigy. He has been credited with a Stanford-Binet score above 210, entered university at four and received an invitation to work at NASA at seven.
Some of the stories around him are disputed, including claims about overseas degrees, which his own parents later contested. We keep him here as a reported case, not a proven one.
10. Marilyn vos Savant
In 1986 vos Savant started writing the Ask Marilyn column for Parade, and she popularised the Monty Hall problem in 1990. She appeared in the Guinness Book of Records for the highest recorded IQ, a category the publication has retired.
Her name stays on the list for the column and the record, not because an IQ score proves anything.
Why did we drop IQ rankings?
Several names in the 2016 version rested on scores from untimed, self-administered tests, and Guinness stopped recording the category because such numbers are unreliable. We also dropped a handful of entries whose claims we could not source or confirm. We prefer proofs and prizes you can verify.
Keep reading
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- Why smart people stay poor: what intelligence does not buy
FAQ
Who is the smartest person in the world?
There is no verified answer. By documented achievement our list puts mathematician Terence Tao first, with a Fields Medal in 2006 and a Breakthrough Prize in 2014.
Who has the highest IQ ever recorded?
Reported scores include Kim Ung-yong above 210 on the Stanford-Binet and Marilyn vos Savant in a Guinness category now retired. Such numbers are unreliable.
Why did the list change from 2016?
We removed entries based on claimed IQs we could not verify, and replaced them with people with public results such as medals, proofs and prizes.
Who is the smartest living mathematician?
There is no official ranking, but Tao, Perelman, Wiles, Scholze and Bhargava have all won or been offered top awards such as the Fields Medal or Abel Prize.
Did Grigori Perelman accept his prizes?
No. He declined the Fields Medal in 2006 and the $1 million Clay Millennium Prize in 2010.
How we put this list together
We ranked each person on the size of the result, how hard it was and how long it has stood, using award records, university pages and encyclopedic biographies. Reported test scores are labelled as reported.
Figures and affiliations are as of October 2026.
Last updated: October 2026.
