I don't know if he has a girl friend. Shall i just ask him out and see?

I am thinking of giving this guy i like my number, he's lovely, we chat but hasn't gone any further yet. I don't want to come right out and ask if he has a girl friend, so if i gave him my number and saw what he said to that.. well do you think that is okay to do? I mean, if he has a girl friend he'll say no (he doesn't seem a bad guy lol) and i'll leave off, right? is this okay? i just don't know! x