help WHAT'S MY RATING?

  I AM wondering I play little chess partner all day long, I think about 30 hours a week... have done so for a while few months...  I play only on hard level etc,

I  have a nice computer so it should play on it's high level etc... I am wondering

if I beat ( LITTLE CHESS PARTNER ON THIS web site )  18 out of 20 games...

   - what would my rating be? Thanks everyone!