The others are right that it is a measure of intelligence, but it is a measure of your natural intelligence, rather than learned intelligence (history, maths, science for example). There is some argument that you can train and improve you IQ, which is true to a certain extent. You can get used to the style of question, which means you are more prepared to answer them, but you still need the natural ability to answer the questions.
In a true IQ test there are no direct math questions. There are no region specific questions, meaning anyone from anywhere in the world could take the test and understand the question without having to have prior knowledge of a specific subject. It is all about your brains ability to analyze, its like a measure of your natural brain power. Most "IQ" test on the internet are not official IQ tests, of which there are several variants. Your average internet "IQ" test has a lot of straight maths in it or things like "Sam has 6 apple and gives 4 to Jane" etc.
It has gone up 5 points since I was 20 when I first did one to now at 31, this could have been due to being quite stressed out when I first did it. I have quite a high IQ but my math ability is very low. I got very low results at school and my mind just goes blank with anything more than basic addition or subtraction.
There are plenty of people that are very low academic achievers but have high IQ's.
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Your neurodiverse (Aspie) score: 153 of 200
Your neurotypical (non-autistic) score: 49 of 200
You are very likely neurodiverse (Aspie)