It's not a simple calculator. Dutch pay will calculate, split every bills paid differently by multiple people and will let you know how to split with minimum transaction!
I went to a trip with my friends and each of us spent different amount of money for buying food, drinks and etc. After the trip, I was struggled with how to spilt all the bills. At that moment, I made Dutch pay and made settlement very easily. What I did was just entering all the bills and DutchPay solved the problem!