Why do some random cute girls smile big at me?

Could be several factors but here's a bit of insight to the female psych. From the time we're able to talk and walk we are taught that we need to be everyone we come across. At least that's how I was raised. When a stranger passes, you smile and say hello or smile and wave if there's glass seperating you. We don't always remember to do this cause as you can imagine, it gets very tiring but we do remember it most of the time.

She thought of something funny, you looked funny, she's listening to a song she likes, she's just being polite, or maybe she thinks you're cute. But more likely, she though of something funny and couldn't repress a smile, or was just being polite.

she's just being nice... I smile at random people al the time. guys and girls both.

I smile when someone looks at me just to be nice

Politeness? Sometimes I notice guys staring at me (I don't think they're checking me out, but it nonetheless makes me uncomfortable) and I just smile to break the uncomfortableness (and it usually works, which is good) Sometimes I make eyecontact with a guy and I don't want to come off as weird or unsocial, so I'll try to smile back. I give the same smile to everyone, cute or not.

Your fly's down...

I smile at people when I know they're expecting me to interact and it just seems like the lesser when compared to saying hi.

I smile when I see a cute guy...sometimes I catch a guys eye in the hall and he gives me a cute smile and I can't help but smile like an idiot.

you must be a cutie then- it could be that they thought of something funny or are having a really good day (cause for me I smile like an idiot when I'm having a good day haha)
-it's when they wink at you when you really know they are into you haha

She obviously hates you and thinks you're fugly /end sarcasm

Now that sarcasm is over, I'm going to add and say that if you get "big" smiles and grins, that's an "ooh you're cute" reaction, or "i'm already in a great mood" smile.but I disagree with the answers who are saying its just politeness because I give small polite smiles to guys I don't think are cute.totally different than big happy smiles. Some girls are just very happy friendly people and will give big smiles to everyone, but if you get those frequently, its more likely girls are finding you attractive

Lmao so no one smiles at ugly people apparently huh

Is just a smile dude. Would you rather for them to flip you off?

Hmm... I have a big problem with this.. I have like social anxiety so I tell myself that I have to smile at everyone and this kinda freaks me out because I'm like "great.. why did you smile? now this guy probably thinks you like him!" lol -.- because I feel like I have to smile and then it makes me look like I wnat them..

Either she does wnat you.. or she's being nice.. you really can't tell lol

But girls do smile at guys they like or want to approach them I guess *shrugs* or she could just be being nice but smiling relaly doesn't hurt shows that she's friendly

well could mean serveral things : she likes you (yay!) or your fly is down... :)

Girls are smilers. I have noticed this when passing guys that I smile at. Guys just don't smile whatsoever, but girls will smile just to acknowledge a guy's presence.
I mean, they might think you are cute too...just smile back. It will make you attractive to them even if they didn't think you were attractive initially.

She's having a good day and she's nice

they think that you are really attractive :)

Maybe because You are a "random cute guy" x) Maybe you just have one of those approachable pleasant faces.

They smile at you cause they think your cute..

Well if it happens a lot then you must be an attractive guy. I personally can keep from grinning like an idiot when I see a hot guy.

Means their either happy, or/and happy to see you. Especially if you're good looking ;)

either she likes you or she is just happy. I smile all the time at people...it is because I am happy and can't help it. Some people think I am crazy lol but its all good.

I smile at strangers because it's polite.

If this is a trend with you...then these females find you attractive. :-D

It means they can't control themselves and immediately want to take off their clothes and suck your d***.

Nah, I'm just kidding. I was just repeating what is probably going on in your head.

Hottie