In conclusion, the highest recorded IQ score belongs to William James Sidis (1898-1944) with an IQ of 250. The second highest recorded IQ score belongs to Terence Tao (b. 1975) with an IQ of 225. However, it is important to keep in mind that these are just two examples of people with high IQ scores and that there are many other people who are also considered to be intelligent. Intelligence is more than just a number and cannot be accurately measured by any single test. Below is the List of Top Highest IQ in the World, o William James Sidis – IQ 250-300 o Terence Tao – IQ 225-230 o Marilyn vos Savant – IQ 228 o Christopher Hirata – IQ 225 o Kim Ung-Yong – IQ 210