if you are applying for 6 months general visitor visa than 12400 PKR
but i tell you if you are applying for the first time than dont waste your money you wouldnt get visit visa if applying from Pakistan these days
ECO(entry clearing officer) have 1000 reasons to reject your application and you have only5 percent chance that you will get visitor visa
and once your visa get rejected than you have to appeal which is very long process now days it take 140 pounds and almost year to process that appeal
So i recommend if u have plan to go uk apply for student visa