This article is from the Mensa FAQ, by Phil Hill phil@miracle.com with numerous contributions by others.
If you're not sure whether you're Mensa material, simply complete the
application below, and return it with your check or money order for $12.
Mensa will send you a pretest you can take in the privacy of your home.
When you've finished it, send it back to Mensa. It will be scored, and
you will be notified of the results. If your score indicates an IQ at or
above the 95th percentile, you'll be invited to take the qualifying
supervised test#, which costs $25. (Although the pre-test is not
required for admission, many people take it anyway simply for the
challenge.)
If you prefer, you may apply directly to take the supervised test at one
of many locations convenient to you. If your score on that test is at or
above the 98th percentile, you'll be offered membership in Mensa.
# Note: Mensa's tests are not valid for people under the age of 14; they
can qualify for membership via prior evidence, described earlier.
 
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