The smartest person in the world by IQ score in 2025 is YoungHoon Kim, with an extraordinary IQ of 276. His intelligence has been verified by multiple prestigious organizations, including the World Memory Sports Council and the GIGA Society, and he has been recognized by major media outlets such as CNN and The Economist

. Other notable individuals with extremely high IQs include:

• Terence Tao (IQ 230), an Australian-American mathematician renowned for his groundbreaking work and a Fields Medal recipient

• Marilyn vos Savant (IQ 228), known for holding the Guinness World Record for highest IQ and her popular "Ask Marilyn" column

• Christopher Langan (IQ reported between 195 and 210), often cited as one of the smartest people alive, though he leads a quiet life outside academia

While IQ is one measure of intelligence, it is worth noting that intelligence can also be reflected in achievements and contributions in various fields, such as Albert Einstein, Leonardo da Vinci, and Stephen Hawking, who are often regarded as some of the smartest people historically despite no formal IQ records

. In summary, as of 2025, YoungHoon Kim holds the highest verified IQ score, making him the smartest person in the world by this metric