Calculating road trip debts: Beyond the Excel Spreadsheet
December 25, 2009 7:44 AM Subscribe
7 friends and I are going on a road trip. At restaurants we usually have one person pay by credit card, and have everyone paying for what they ordered to the individual. Oh, and not everyone is gonna be at every event, so having one individual pay for everything on the trip is impossible. And it should redistribute debts so at most each person only needs to make 1 payment to another person. What is the best free method for calculating who pays whom?
posted by jytsai to Grab Bag (18 answers total) 3 users marked this as a favorite
There are many websites, but the 5 or 6 I've tried so far all have at least one or more of the following problems:
1) Assumes that at restaurants everyone goes dutch and splits bills equally. (Not usually how my group does things; people will complain.)
2) Assumes that you are the person who pays for everything.
3) Limits free access to situations that have less than 8 individuals.
4) Does not optimize payments. (In theory, it should be possible to reassign debts from one individual to another so that each person only needs to make one payment to one person.)
Here is an simplified example:
4 people, 3 events...
*Person 1 paid for gas ($36), split among the three. Person 4 did not participate.
*Person 2 paid for a meal, where person 1's order was $6, person 2's was $8, and person 3's was $10. Person 4 did not participate.
*Person 4 borrowed $10 from Person 3.
I want to be able to plug how much each person owes at each event, who paid, and have it tell me something like:
Person 2 owes Person 1 $6.
Person 3 owes Person 1 $12.
Person 3 owes Person 2 $10, but since person 4 owes him $10, person 3 pays nothing and transfers the debt so...
Person 4 pays person 2 $10.