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Split the cost: who pays whom

For housemates, families, friends on a trip, and anyone sharing rent, bills, food or a ride. Write who is sharing, then each thing that was paid for: how much, who paid it, and who shares it. The page adds up what each person paid and what each person’s part comes to, and gives a short list of payments that leaves everyone even. There is no account and no price, and nobody else has to sign up for anything.

Private by design. Nothing you type is sent anywhere: not the names, not the amounts. What you add is kept in this browser on this device from the first time you press Add, and one button erases it. The other people do not see it unless you show them, print it or send them the text. If other people use this phone or computer, they can open this page and read it. This page runs no analytics or tracking. How we handle privacy.

This tool needs JavaScript. The same sum on paper: for each person, add up what they paid; divide each cost by the number of people sharing it and add up each person’s parts; the difference between the two is what that person gets back or pays.

Good to know

How it works

Who is sharing: from 2 to 12 names. A person can be added later; the costs already written down stay shared by the people who were ticked.
Each cost: what it was, the amount, who paid it, and a tick beside everyone who shares it. Everyone is ticked to start with.
A cost only some people share: untick the others. The person who paid does not have to be one of them.
Money someone already handed over: write it as a cost paid by the person who gave it, shared only by the person who got it. Call it something like “Cash to Ana”.
Who pays whom shows the payments, then each person with what they paid and what their part comes to.
Print, Copy as text and Download (.txt) give the result to send to the others or to keep. A copy off this device is the only backup there is.

How the page counts

Whole cents. Every amount is counted in cents, so nothing is lost to rounding.
A cost is divided evenly among the people sharing it. $84.30 among three people is $28.10 each.
Cents that will not divide go, one each, to the people sharing that cost in the order of the list. $61.00 among three is $20.34 for the first person and $20.33 for the other two. No two people sharing a cost are ever more than one cent apart on it.
A person’s difference is what they paid minus their parts. Above zero, they get money back. Below zero, they pay.
The payments: the person furthest behind pays the person furthest ahead, as much as the smaller of the two amounts, and the page does that again until everyone is at zero. There are always fewer payments than people. It is one way to get everyone even; there can be others.

An example, worked by hand. Ana, Ben and Cruz share a place. Ana paid $84.30 for groceries for all three. Ben paid the $61.00 electric bill for all three. Cruz paid $24.00 for a pizza that only Ana and Ben ate.

Paid: Ana $84.30, Ben $61.00, Cruz $24.00.
Parts: Ana $28.10 + $20.34 + $12.00 = $60.44. Ben $28.10 + $20.33 + $12.00 = $60.43. Cruz $28.10 + $20.33 = $48.43.
Differences: Ana gets back $23.86, Ben gets back $0.57, Cruz pays $24.43.
Payments: Cruz pays Ana $23.86, and Cruz pays Ben $0.57.

The names in the example are made up. A program checks this example, and 400 made-up lists, every time the page is built.

What an even split does not know

It does not know what is fair between you. Dividing evenly is one way to share a cost. People also share by income, by room size, or by who used what, and this page does not do those.
It does not know who used more: the long showers, the bigger room, the food one person does not eat. Unticking a person takes them out of a cost; there is nothing in between.
It does not know whether an amount is right, or whether a cost was written down twice.
It is not an agreement. Nobody has signed anything, and this page cannot make anyone pay.
It does not move money. The payments are a list; paying is up to you.
It holds up to 12 people and 200 costs on this device, and it does not move to another phone or computer by itself.

If there is not enough to cover your part

On this site: Help with money has places to turn when the money does not cover the month, and Help with food is for when there is not enough to eat.
Calling 211 reaches a local helpline in most of the U.S. that knows what help is near you.
If someone you live with hurts, threatens or controls you: When home isn’t safe.

Tools that go with this

House agreement: what you agreed about living together, shared money included, on one page.
Bills: one real month, each bill with its due date, ticked off when paid.
Money plan: one month of money on one page.
Shopping list: the total of the list before the register, and the cart added up as you go.
Make peace: a hard talk or an apology, planned before you say it.
All the free tools, and how to save them on your phone.

Arithmetic, not an agreement and not advice. This tool adds, subtracts and divides the amounts you type. It does not know what you agreed with each other, and it cannot tell you what is fair. If anyone is in danger, call 911. If things are so heavy that you are thinking about ending your life, call or text 988 (in the U.S.), or open Get help now.

The tool and the wording around it were written with AI (Claude) for Scarlet Beast (our AI policy); the names, the costs and the amounts are yours. There is no AI inside this tool: it only adds, subtracts and divides. It has been checked by a program, not yet used by people sharing a home. What it keeps is listed on My data on this device. Also in Spanish: Dividir gastos; both pages keep the same list on this device. Found a mistake? Email [email protected].