What time would be right to ask her out to be my gf?

So i've met this girl who im actually so into. I met her at school, and mustered up the courage to ask her out. She is really beautiful, funny, smart, etc. We been on a couple of dates and i always have the best time with her. I feel alive with her and she is soo fun to be around. So we shared our first kiss about 2 days ago. I know we should keep dating more before i ask her, but when would be the right time? I really like her, and im pretty sure she feels the same. any advice?