http://tvtropes.org/pmwiki/pmwiki.php/JustForFun/KinseyScaleOfTropes

The Kinsey scale, named for Alfred Kinsey , a bi ologist, invented a seven-point-scale used to rate a person's orientation from 0, or completely heterosexual, to 6, or completely homosexual. This algorithm here shows where our many tropes relating to sexuality would fall on the scale.

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Note that the above list, especially when viewed under the assumption of Everybody Has Lots of Sex, makes people sound a lot hornier than they really are. It was for this reason that Kinsey later added an 8th category:

Another scale, a bit more detailed in explanation, works on percentages and ratios. It was not invented by Kinsey, but it is still applicable. Note that this scale applies only to the hetero/homo dichotomy, does not include Asexuals , and is referring to preferences and perceived sex, rather than self-identified gender. For instance, a non-binary (person with a gender neither male nor female) who presents as female is female under this scale, while if they presented as male instead, they'd be considered male.

100/0: A purely heterosexual person who is incapable of noticing attractiveness in their own sex, or even actively dislikes/considers them repellent. These people are extremely rare, though they do exist. There are more straights who claim this than those telling the truth. After all, you'd be a pretty crappy "alpha male" if you're unable to tell whether or not another man would be a threat to your harem.

90/10: A purely heterosexual person who is capable of recognizing attractiveness in their own sex, though only in the aesthetic sense.

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80/20: A purely heterosexual person who recognizes attractiveness in their own sex in more than the aesthetic sense, but is not personally attracted to them.

70/30: A bisexual person who may identify as heterosexual and who recognizes attractiveness in their own sex, aesthetically and otherwise, and may even be attracted to members of their own sex, but strongly prefers the opposite sex.

60/40: A bisexual person who recognizes and acknowledges attractiveness in both sexes, and is attracted to both, but has a slight preference towards the opposite sex.

50/50: A bisexual person who finds both sexes equally attractive. See also Everyone Is Bi, Anything That Moves.

40/60: A bisexual person who recognizes and acknowledges attractiveness in both sexes, and is attracted to both, but has a slight preference towards the same sex.

30/70: A bisexual person who may identify as homosexual and who recognizes attractiveness in the opposite sex, aesthetically and otherwise, and may even be attracted to members of the opposite sex, but strongly prefers their own sex.

20/80: A purely homosexual person who recognizes attractiveness in the opposite sex in more than the aesthetic sense, but is not personally attracted to them.

10/90: A purely homosexual person who is capable of recognizing attractiveness in the opposite sex, though purely in the aesthetic sense.

0/100: A purely homosexual person who is incapable of noticing attractiveness in the opposite sex, or even actively dislikes/considers them repellent. These people are extremely rare, though they do exist. Many Straw Feminists seem to fit here. See also Het Is Ew.