IQ is a problematic measure of intelligence. Many have never been tested, while others have taken the test many times to improve their scores. Still, psychologists consider it the best measurement of intelligence out there.
So who has the highest score?
The World Genius Directory, created by Dr. Jason Betts, is a fluid list of the world's top mind compiled from certified IQ tests sent in by listees. Betts says his site is the definitive ranking.
"Other [IQ] websites had existed, and some still do, but they are based and limited by local constraints, for example, written in Spanish, for Europeans only, only accept their friends' tests, and so on," Betts told us in an email. The directory "has no preferences nor bias, except test quality."
The average score on an IQ test is 100. Most people fall within the 85 to 114 range. Any score over 140 is considered a high IQ. A score over 160 is considered a genius IQ.
If you're wondering, Betts includes himself on the directory. His IQ is 168.
Courtesy: Ivan Ivec16. Ivan Ivec has an IQ of 169
Nationality: Croatian
Ivec specializes in high end IQ tests, competitions and statistics. He's a member of Croatia's MENSA and teaches advanced mathematics.
Ivec has puzzle competitions and other tests of academic strength on his website.
Courtesy: Gaetano Morelli15. Gaetano Morelli has an IQ of 169
Nationality: Italian
Gaetano, called "Tany" for short, is an engineer at an Italian firm and the author of a book about Albert Einstein's Theory of Relativity.
He's a member of at least 20 high IQ societies and founded his own, the STHIQ.
His hobbies include bridge, chess and fishing.
14. Jorge del Fresno Viejo has an IQ of 170
Nationality: Spain
Jorge is a member of several IQ societies including Morelli's STHIQ society, the Universal Genius Society and Epida.
(Photo not available.)
LinkedIn13. Mick Dempsey has an IQ of 171
Nationality: British
Dempsey has a degree in forensic psychology from London Metropolitan University. He is a youth support worker at Hertfordshire County Council, according to his LinkedIn profile.
Dempsey also enjoys jazz, Faulkner, the Everton soccer club and films including Pulp Fiction, according to his Facebook page.
HELLIQ Society12. Marc Nydegger has an IQ 171
Nationality: Swiss
The 20-year-old prodigy from Fribourg, Switzerland is a scientist and video game designer, according to his profile at Hall of the Ancients.
The profile says his favorite food is "knowledge" and his favorite drink is "intelligence." 
HELLIQ Society11. Santanu Sengupta has an IQ of 174
Nationality: Indian
Sengupta holds an an MBA and bachelor's in Aerospace engineering.
When he's not working the equity property desk for a financial services firm, the 34-year-old enjoys traveling, stimulating discussions, solving puzzles and good food. Sengupta's favorite drink, by the way, is vodka.
