As I stated in a previous post:

Many years ago, I noticed that IQ was correlated with a great many physical and demographic traits such as head size, height, income, education, etc. This gave me the idea of trying to estimate peoples’ IQs based on bio-demographics. A member of Prometheus society brilliantly suggested that “multiple regression” would be the classic application for my idea, and he also suggested that I use religiosity as one of the demographic traits.

Well it turns outs psychologists have been using demographic traits like education and occupation to estimate premorbid IQ in people suspected of dementia for years, but they don’t include biological traits except for race. I thought it would be interesting to use a wide range of bio-demographic traits so using data from 144 Canadians (age 26 to 76) I created an equation to estimate your IQ. The sample was heavily skewed towards my demographic (Ontario men in their thirties) but the formula might still work on working age North Americans in general.

This formula has been substantially revised and adapted for use in Americans.


Start by assuming your IQ is -1.251, and then add or subtract based on the following 25 instructions. Be honest or your estimate will not be accurate.


1. If you graduated from elementary school, add 6.212 points

2. If you graduated from high school, add another 6.212 points

3. If you have a university degree, add another 6.212 points.

4. If you have a graduate degree or attended an elite college or high school, add another 6.212 points.

5. If you both attended an elite college AND have a graduate degree, add yet another 6.212 points.

Head Size

6. Multiply your cranial circumference (in inches) by 2.768 and add the resulting number of points.


7. Multiply your height (in inches) by 0.418 and add the resulting number of points


8. Multiply your weight (in pounds) by 0.0927 and subtract the resulting number of points


9. If you’re less than half-black, add 2.666 points

10. If you’re less than a quarter black and less than a quarter Native American, add another 2.666 points

11. If you’re more than 75% Northeast Asian, or more than 50% Ashkenazi Jewish, add another 2.666 points

12. If you’re more than 75% Ashkenazi Jewish, add yet another 2.666 points

Media preferences

13. Which of the following do you most prefer for entertainment: a) fun TV shows like sitcoms, reality TV, game shows, sports, and popular talk shows, b) intellectual TV shows about science, history or politics, c) fun books like romance novel or thrillers, or d) intellectual books like literary novels or academic texts.  If you chose “a” add 0 points,  if you chose “b” add 3.451 points, if you chose “c”, add 6.902 points, and if you chose “d”, add 10.353 points.


14. If you’re male, subtract 5.1 points


15. Multiply the number of figures in your yearly pre-tax income by 1.869 and add the resulting number of points.  If you’re retired, use your peak earnings, adjusted for inflation. If much of your earnings go into your business or if you’re too rich to have a conventional income, simply divide your individual net worth by ten to approximate your income.


16. If you believe in God, subtract 3.901 points.

17.  If you’re a creationist who does not believe in evolution, subtract another 3.901 points.

Political conservatism

18. Which of these U.S. political parties would you most like to see in power: The Green party, the Democrats, or the Republicans? If you picked the Green party, subtract 0 points, if you picked the Democrats, subtract 3.405 points, and if you picked the Republicans, subtract 6.81 points.


19. If you’re an alcoholic, subtract 2.282 points


20. If you’re a smoker, subtract 2.282 points


21. Multiply the number of years you’ve been alive by 0.194 and add the resulting points

Birth Order

22. Multiply your birth order by 0.885 and subtract the resulting points. So if you’re your biological mother’s third born, multiply 3 by 0.885 and thus subtract 2.655 points.

And your IQ is…

23. Subtract 100 from all your points

24. Divide by 0.8

25. Add 100