It is normal for a child to have an IQ score of 70 or above. The range of IQ measurement is generally from 46 to 160, with most people having an IQ level of 100. The internationally accepted method is to set the IQ level of children with extraordinary intelligence at an average of around 130.

The formula for IQ is: IQ = mental age/actual age × 100. For example: a child with an actual age of 8 years and 2 months, if his mental age is 8 years old, his intelligence quotient (IQ) is IQ = 8 years / 8 years and 2 months × 100 = 98