How to tell a nice guy from a good guy?

[Margreet]

Just watch how he treats other people, and how he talks about them when they aren't around. How does he treat little kids? How does he treat animals? His mom? His sisters?

Talk to his exes, if you dare. They'll tell you the truth, like it or not.

[Zevispaz]

In my experience:

Nice guys
* Doormats, they're insecure. They'll go along with every single one of your ideas. They'll let you push them around and walk all over them. If a guy is constantly letting you have your way with no fight whatsoever, ditch them. They also think being nice is not fighting back when someone has wronged them. They'll also resent doing favors for other people.
* Not confident in themselves. They'll be clingy in have to be around you every single second of the day. They'll bend over backwards just to impress you, and feel like they need to prove themselves every day.
* Passive aggressive. They never get angry with you, but take it out in a different way. Like guilting you or sabotaging your plans on "accident". This goes hand in hand with being a door mat. They expect you to be a mind reader, or take initiative, so they don't have to take any of the risk.
* Manipulative. They'll manipulate how you feel, what you do, where you go, who you hang with. If you don't follow their whims, they'll act like wounded animals and resort to passive aggressive behavior.

Good guys
* Confident. They're secure with themselves, and they respect themselves, so they'll expect you to respect them right back. They already know their value and if you like them, awesome. If not, oh well. They'll stand up for themselves, they won't let people walk all over them.
* Independent. They won't rely on your for their happiness. They'll be happy on their own, which won't put any pressure on you. When you do your own thing, they won't be upset by it.
* Genuine. They treat everybody with the same level of respect, and they don't hold resentment for doing favors for people because they only do favors if they want to, not because they need to prove how "nice" they are.

So basically:

Confident + Nice = Good Guy
Insecure + Nice = Nice Guy

I think it's really easy to spot when someone is being insincere and when someone is being genuine, in only a few minutes of meeting them. It's more intuition, so I don't know what the tells are, but I'm very rarely wrong about it.

I guess in the mean time, just be independent and confident in yourself. Nice guys hate independent women because they're so insecure. It won't last if you keep your schedule and hobbies without giving them up for them. That in itself should genuinely weed out the jerks.