Sorry, I've had both my kids go through the WISC-V "IQ" test in the last few years and there's no single "intelligence" number that comes out of that that would be meaningful for employment. It measures all sorts of things and you can be off the charts high in one kind of mental / reasoning skill while being average or below average in others and yet that still might tell you nothing about how well someone writes code at a job.
Most of us aren't doing intense mathematical reasoning stuff at work. Sometimes we have to, but most of the time the actual amount of novel algorithm stuff being done pales in comparison to "synthesize this knowledge from 10 different sources and evaluate the best way to integrate that into a reasonable solution."
I don't think coding tests are a good substitute for that, and an IQ test would not give you a clear answer there either.
Most of us aren't doing intense mathematical reasoning stuff at work. Sometimes we have to, but most of the time the actual amount of novel algorithm stuff being done pales in comparison to "synthesize this knowledge from 10 different sources and evaluate the best way to integrate that into a reasonable solution."
I don't think coding tests are a good substitute for that, and an IQ test would not give you a clear answer there either.