What this calculator does
Living with roommates or traveling with friends means one person often pays a bill for everyone. Add the people sharing, then each bill with who paid it and how to split it. The calculator shows what each person paid, their fair share, who owes whom and the fewest payments that settle everyone up. Names and descriptions stay on this page: nothing is saved or sent.
How it is worked out
For a bill split equally, each person's share is the amount ÷ the number of people. For a bill split by share weight, each person's share is the amount × their weight ÷ the total of all weights. A person's balance = what they paid − their fair share. Then the person who owes the most pays the person who is owed the most, and so on, which needs at most one payment fewer than the number of people.
Example: three roommates share $1,800 rent by weight (1.2, 1, 0.8), and $140 electricity, $65 internet and $230 groceries equally. Person 1 paid the rent and the groceries, person 2 the electricity and person 3 the internet. Person 1's fair share is $865 and they paid $2,030, so they are owed $1,165; person 2 pays them $605 and person 3 pays them $560.
Splitting rent fairly
- Splitting rent equally is simplest when the rooms are alike.
- When one room is bigger or has its own bathroom, give it a higher weight, for example 1.2 against 1.
- Utilities and household supplies are usually split equally, but you can choose for each bill.
- Put the agreement in writing, including the security deposit and what happens when someone moves out.
Frequently asked questions
How do you split bills between roommates?
List every shared bill and who paid it, decide whether each is split equally or by room size, and settle the difference each month. The calculator does the math and lists the payments.
How do you split rent by room size?
Give each person a weight, such as 1.2 for the larger room and 1 for the others, and choose "by share weight" for the rent. Each person pays the rent × their weight ÷ the total weight.
Why do I see fewer payments than people?
The settle-up list pairs the people who owe with the people who are owed, so a group of n people never needs more than n − 1 payments.
Is my information saved?
No. Names, descriptions and amounts stay on this page while it is open; they are not stored, sent or put in a link.