1. Jacob Barnett: IQ 170

Jacob Barnett was  diagnosed  with moderate to severe autism at two years old, and doctors predicted he’d never learn to tie his own shoes.

Needless to say, he’s mastered dressing himself. The American child prodigy finished grades six through twelve in less than a year, then went to college at age ten.

He was a published physicist  by the time he was 13.

Now he’s  working toward his PhD  at age 19.

2. Judit Polgár: IQ 170

The Hungarian chess master is considered the best female chess player of all time.

When she was 15 years and 4 months old in 1991, she was the  youngest player  to become an International Grandmaster.

She’s  reported  to have an IQ of 170.

3. Rick Rosner: IQ 192 to 198

Rick Rosner has taken  more than 30 IQ tests, revealing his IQ is between 192 and 198, depending on how the tests define their scores.

Before the allegedly second-smartest man in the world became a TV writer, he worked as a bouncer, stripper, and nude model.

He famously  sued  ABC network for a faulty question after losing  Who Wants to Be a Millionaire  at the $16,000 level, but he lost the case.

4. Evangelos Katsioulis: IQ 198

With a score of 198, Evangelos Katsioulis, MD, MSc, MA, PhD, has the highest tested IQ in the world, according to the  World Genius Directory.

The Greek psychiatrist also  has degrees  in philosophy and medical research technology.

5. Sho Yano: IQ 200

American physician Sho Yano started college at age nine, and earned an MD and PhD  by the time he was 21.

He has a black belt in tae kwon do and started composing music when he was four, but he’s put his focus on  child neurology.

6. Nathan Leopold: IQ 200

The infamous Nathan Leopold had an IQ of 200 and spoke nine languages by age 18, but he didn’t use his intelligence for the greater good.

When he was 19, he and an accomplice were  arrested for murder  in 1924 after trying to commit the “perfect crime.”

Leopold spent 33 years in jail before being released on parole.

7. Marilyn vos Savant: IQ 228

When Marilyn von Savant was ten years old, an adult-level Stanford-Binet test revealed she had an  IQ of 228, which later landed her a Guinness World Record until the company removed the category in 1990 because the numbers are considered inexact.

She’s been answering philosophical and mathematical questions for  Parade  magazine readers in her “Ask Marilyn”  column  since 1986

8. Ainan Cawley: IQ 263

This Irish child genius is  projected  to have an IQ of 263.

At eight years old, he was already taking third-year chemistry courses at Singapore Polytechnic, and by the time he was nine, he’d memorized the first 518 decimal places of pi.

Now 18, he seems to have a knack for entertainment, having written the script and composed music  for a short film called  Reflection  at age 12.  

Written by Marissa LaLiberte. This article first appeared in  Reader’s Digest. For more of what you love from the world’s best-loved magazine,  here’s our best subscription offer.