People often talk about very high IQ scores, often referred to as genius IQ scores, but what exactly do these numbers mean and how do they stack up? It's not always easy to understand what IQ test scores mean. Most professional tests, like the culture fair intelligence test or the classical intelligence test, don't only give you a specific IQ score, they also mention an IQ range.
This range shows you that your score may vary within this IQ scale, due to error of measurement and because circumstances under which you take a test might be of influence. The average IQ score is always 100, and your personal score tells you your IQ ranking compared to that. IQ scores are based on comparisons with other people who took the test: the norm group.
As 100 is the average score, your score tells you how your IQ score ranks compared to other people. There is no such thing as a 'normal iq range', although you can distinguish categories like average intelligence. Most IQ classifications tend to take care in naming groups the distinguish. So, if you're looking to find what a genius IQ level is, 'very gifted' could be the phrase you are looking for.
The properties of the normal distribution apply to IQ scores:
of IQ scores fall between 90 and 110
of IQ scores fall between 85 and 115
of IQ scores fall between 70 and 130
of IQ scores fall between 60 and 140
Lewis Terman (1916) developed the original notion of IQ and proposed this scale for classifying IQ scores.
|140+ IQ Scores||Genius or Near Genius|
|120 - 140 IQ Scores||Very Superior Intelligence|
|110 - 119 IQ Scores||Superior Intelligence|
|90 - 109 IQ Scores||Normal or Average Intelligence|
|80 - 89 IQ Scores||Dullness|
|70 - 79 IQ Scores||Borderline Deficiency|
Genius IQ is generally considered to begin around 140 to 145, representing ~.25% of the population (1 in 400).
|115 - 124 IQ Scores||Above Average (e.g., university students)|
|125 - 134 IQ Scores||Gifted (e.g., post-graduate students)|
|135 - 144 IQ Scores||Highly Gifted (e.g., intellectuals)|
|145 - 154 IQ Scores||Genius (e.g., professors)|
|155 - 164 IQ Scores||Very Genius (e.g., Nobel Prize winners)|
|165 - 179 IQ Scores||High Genius|
|180 - 200 IQ Scores||Highest Genius|
5% of people have an IQ under 70 and this is generally considered as the benchmark for "mental retardation", a condition of limited mental ability in that it produces difficulty in adapting to the demands of life. Severity of mental retardation can be broken into 4 levels.
|50-70 IQ Scores||Mild mental retardation (85%)|
|35-50 IQ Scores||Moderate mental retardation (10%)|
|20-35 IQ Scores||Severe mental retardation (4%)|
|< 20 IQ Scores||Profound mental retardation (1%)|