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Most IQ numbers online have no source at all.
This site fixes that two ways: reasoning tools that show their working, and famous IQ claims traced back to whoever first printed them.
Question 15 of 24 · Numerical reasoning
What number comes next?
235813?
Pick one. The answer and the reasoning appear here.
The tools
Three of them. None ask for anything.
One is a real reasoning test. Two are for fun, and say so on the page rather than in the small print.
Real IQ Test
24 questions across pattern, verbal, numerical and spatial reasoning. Wrong answers cost a third of a point, so guessing cannot lift the score.
02Twitter IQ Checker
Score any X handle, unlock a persona, or put two handles head to head. Reads the handle text only, never the account.
03IQ Checker XYZ
The username version for any platform, plus a mode that builds higher-scoring handle ideas from a name you give it.
Fact checks
The number everyone repeats, and the one the evidence supports.
Every figure below was traced back to its first appearance in print. Where the trail ended at nothing, we say so.
Bill Gates
His 1590 SAT converted straight across gives 160. That skips regression to the mean. See the working →
George W. Bush
The 91 came from a 2001 chain email crediting an institute that has never existed. See the real study →
Albert Einstein
Never tested. Printed guesses have run from 192 to 207, so today’s 160 is the lowest of them. Where it came from →
J. Robert Oppenheimer
Four figures circulate, 55 points apart. Only the lowest is built on anything checkable. Which one holds up →
Shakespeare
Credited to Cox’s 1926 study, which deliberately excluded him for lack of childhood records. The full picture →
How the score is worked out
Why a lucky guesser cannot beat this test.
Most free tests count correct answers and stop there. That is why so many of them hand out 130s.
Four options means guessing already scores
Click at random through 24 questions, understanding nothing, and chance alone gives you about six correct. On a test that just counts right answers, those six are free points.
So a third of a point comes off each wrong answer
This is the standard correction for guessing, and the arithmetic lands exactly where it should: at six correct out of 24, the penalty cancels the lucky points and your corrected total is zero.
Then it goes on the same scale real tests use
The corrected total is mapped onto the 100/15 scale, where 100 is average. Scores floor at 70, because anything at or below chance is not measuring anything and should not pretend to.
One person writes and checks all of this.
I build the tools, trace every claim to its original source, and log my own corrections in public when a reader catches something.
How claims get checked here →