/sci/ - Science & Math

What’s the most credible, free online IQ test /sci/ ?

Lets say you have a slider that's 20 or 30 IQ points in length and you move it across the bell curve to compare two individuals at the opposing points of the slider. What is the difference in the difference? For example, to a person with an IQ of 100 someone who is 80 would appear to be somewhat mentally slow, but the difference between 100 and 130 isn't as great, and I'm guessing it wouldn't preclude the possibility of those two individuals being friends? Does a person with 130 appear to be mentally slow to someone who is 160? Or does the difference between individuals diminish as IQ increases? What about a 140 and a 170. Is the difference less significant at the high extremes?

126 is really high
most people who are actually remembered are probably lower