How can I know if I'm bisexual if I had only one-gender experiences?

Being bisexual doesn't have to reflect the experience you've had. It describes your potential to be attracted to different genders. If you feel you can be attracted to more then one gender, and bisexual feels right to you than you are bisexual and your sexuality is valid.

Because behavior is not orientation. Experiences only help you figure out if you like those experiences. If you have felt a pull, hunger, or allure toward specific people in which you wanted to partake in sexual activities with them, and those people were of two or more different genders, then bisexual may be a good a label. Polysexual and pansexual may also interest you. Orientation describes only which genders you feel attraction toward and, when it comes to the asexual spectrum, at what frequency / under which conditions. Your attitudes toward and experiences with sexual and/or romantic activities hold no sway over that. For example, someone can be repulsed by sex and never want to have sexual relations, but can still feel attraction toward others. They just may not want to act on that attraction. Another way to think of it is to ask: Does someone who is straight need to have experiences to confirm that they are straight? Odds are, they just know they're straight. So why can't someone just know they're bi? You know how you feel better than anyone else, and no matter what, those feelings are real and valid.

Sexuality is a matter of opinion more than a matter of experiences. Being bisexual only means that you feel sexual attraction to two genders and so having experience with only one gender does not invalidate your sexuality in the slightest.

Would you ask an inexperienced straight or gay person the same question? Sexual and romantical orientation isn't based on relationship or sexual experiences but sexual and romantical attraction - keyword here is ATTRACTION. It's not the exact same thing, esp. since I am not sexually attracted to animals, but try seeing it this way: I think both snakes (a reptilian species) and dogs (a mammal species) are pretty, but I've only ever petted dogs and not any reptiles, but does this mean I only think dogs are pretty because I have petted them and not snakes? No, absolutely not, I still think both are beautiful animals!

You will know if you are Bi because you will be sexual attracted to both males and females. you dont need to have experences with both to understand you feelings

i think that you know what sex you like when you find one of the sexs or both of the sex attractive in that way, once you have an experience you will now for sure but its common for teenagers to have phases or want to have experience with the same sex

Really, it's about how you feel. Do you get sexual vibes when a woman touches you? How about a man? If both are a yes, then you're bisexual. You don't need to necessarily have sex with both sexes before you know.

Try looking at it with a different perspective. For example, a heterosexual woman may believe she is 100% into men only, yet she's never been with a woman. So how could she know for sure that she /isn't/ bisexual? Try this with your friends! It's tricky to fully understand and explain, but there are some things that we just innately know about ourselves. Your emotions and feelings are real and valid. You can be bisexual and only ever be with one gender if that's just how things work out.

Your orientation is not defined by your experiences, but rather by the attraction you feel. If you also feel attracted by the gender you had no experience with, if you have a positive reaction imagining yourself with them, if your feelings and emotions tell you that you could be attracted by more than one gender, it's enough to identify your orientation. You may know that you're bisexual even if you have only one-gender experiences, because it's all about what you feel, not what you do.

If you've had sexual and/or romantic thoughts about more than one gender, there is a good chance you are bisexual :)