Despite its kinks, the Big 5 factor model of personality is still one of the best validated. Want to find out where you score on extraversion and more? Take it for free: (I do not work for them, I'm just a psychologist who hates the MBTI) personalitytest.net/ipip/

IPIP NEO - The five factor model of personality.

IPIP NEO - The IPIP-NEO (International Personality Item Pool Representation of the NEO PI-R™)