No matter what dating services and sites might lead us to believe, there is no secret equation that will say whether two people are a sexual match. Sex is too individual, complex, and dynamic to be simplified like that. Recognizing that sexual compatibility can be a serious concern (as well as a passing curiosity), here is a quiz that may give some idea about what makes two partners pair well – and what can lead to disappointment down the road.

Physical attraction may fade over time, but having that initial desire is important. “People will make the mistake of thinking, ‘this is a great guy’ or ‘they look great on paper,’ but if there isn’t a basic physical attraction, it’s not going to work,” says Tiger Devore, clinical psychologist and certified sex therapist. For some people, physical attraction is based solely on appearance, but there are harder to explain elements of physical attraction that are powerful too. Consider online dates who match their profile pic exactly but still disappoint the moment they walk through the door.

Some research has suggested that scent may help inform humans’ choices in sexual partners. The theory is that scent can communicate information about immune system genes, facial symmetry, and even dominant behavior. The evidence for all of this, however, is still far from certain.

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Sexual compatibility shouldn’t be confused with relationship compatibility. People can have a great time together sexually even if they don’t care for each other’s company beyond that. Liking a person’s personality or having similar interests can be a nice plus, however. “Those things may not play into initial attraction at all, but will play strongly into longer-term attraction, and maintenance of intimacy over time,” says Devore.

Many people have to work at being present during sex. Preoccupations about jobs, chores, and sexual prowess can get in the way of a good sexual experience for both partners, even if only one of them is preoccupied. People can often sense when their partners are distant during the act, and this can dull otherwise great sexual chemistry. Those partnerships that can talk about these stresses can make progress toward achieving more focused (and then more satisfying) sex.

A common mismatch between couples is the how passionate they are sexually. Devore says that many women feel the need to hold back in bed due to pressure to not come off as “slutty.” This can be disappointing and discouraging for guys. “A lot of times those physical demonstrations have a lot to do with a man feeling desired […],” says Devore. “If those things aren’t there, then sexual interest is going to fade very rapidly.” A tricky double-standard worth addressing if it might be the source of problems for you and your partner.

b. I’m terrified of telling her what I want or finding out she wants something I can’t do for her. (0 points)

Nothing benefits a sex life more than understanding it. Each partner should take some time to know what they want sexually and what their partner wants. Most people won’t have a full picture of everything they’d like to try (or avoid), but being open to talking about sex can get couples a very long way toward blissful satisfaction. This can also help people avoid challenging surprises later, such as the discovery of uncommon desires that even a committed loving partner can’t accommodate.

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Size doesn’t really matter as much as most men are lead to believe (but there is one situation that can be a deal breaker: a penis that’s too big. Most women can accommodate a lot down there, but there is the rare situation where parts just don’t work together, and it can become a potentially painful issue.) “Sometimes a loving couple has to face a breakup if intercourse never becomes easy or comfortable for the female if the man’s penis is too large for her,” says Devore.

Foreplay cannot be overlooked. It’s true that some people like it more than others. It’s also true that foreplay can be more than physical. Helping around the house, compliments, or giving a massage all count too. friendfinder If couples aren’t able to coordinate their foreplay wants and needs, it can become a critical issue. Believe it or not, Devore says problems with foreplay and romance often stem from differences in schedules.

The classic evolution of sexual relationships is that they get routine and stale over time as a result of neglect. “[People] do have to pay attention to their sex life or it tends to become very constricted, and then not very interesting, and then not very often,” says Devore. Like work, kids, and bills, relationships require effort and attention for the best outcomes.

A solid match with an impressive level of partnership. Similar desires, thoughtful effort, and some biological luck pay off. But don’t get too cocky. Maintaining this level of compatibility will probably require extra work. “If they want to maintain that level of mutual excitement, they are going to have be good and honest communicators of their various interests and distractions sexually,” says Devore, “and be supportive of mutual experimentation, at least in fantasy (if they have a monogamous agreement).”

This level of sexual compatibility is probably where many couples are or will be at some point. “All couples’ sense of attraction to one another waxes and wanes,” says Devore. “Sexual tastes may change over the life term, and they may go through periods of being less compatible.” When sexual compatibility feels like it’s at a low, Devore says people might need to make some moves to spice things up. Unless someone is hiding a major sexual curve ball, there shouldn’t be anything to worry about. Even small pushes to address lackluster sex (try these 10 ways to spice up your sex life) can lead to fantastic improvements.

There are some signs that things could be better. If everything but the sex is great, don’t worry too much. Try to figure out what the problem might be. Stress, being uncomfortable exploring and discussing sex, or simply not giving a sexual relationship some TLC are common issues. If the problem seems too big to handle, a sex therapist might be able to offer some techniques to work through incompatibility or at least provide an objective perspective on the situation. If the incompatibility is more personal or emotional, Devore says a marriage or relationship counselor is more appropriate.