# Debt simplification calculator: the fewest payments for four people

Canonical URL: https://www.evenoutapp.com/tools/debt-simplification-calculator
Updated: 2026-10-06

Enter up to six IOUs among four people, A to D. The calculator finds each person's net balance, settles any pair of exact opposites with one payment, then has the biggest debtor pay the biggest creditor until everyone is at zero. For four people that is the fewest payments possible. The example turns six IOUs worth $175 into 2 payments worth $95.

Key points:
- A person's net is the IOUs owed to them minus the IOUs they owe. The four nets always add up to zero.
- Four people never need more than 3 payments, and at most 2 when one debtor owes exactly what a creditor is owed.
- In the example, six IOUs worth $175 become 2 payments worth $95: A pays B $45 and C pays D $50.
- For up to four people this rule cannot be beaten. Larger groups can hide subgroups that settle among themselves.
- Only each person's net is fixed. An app can show a different set of payments that clears the same nets.

## When to use the debt simplification calculator

Use it when a few people owe each other in several directions and you want the fewest payments that clear everything. Enter up to six IOUs among four people, called A, B, C and D. Each IOU has who owes it (1 for A, 2 for B, 3 for C, 4 for D), who is owed (the same numbers) and an amount. An amount of 0 means the IOU is ignored.

As of October 2026, Splitwise describes its Simplify Debts setting as one that "restructures who owes whom within a group to minimize the total number of payments needed for everyone to settle up". This simplify debts calculator has the same aim for IOUs you type in by hand, and it does not read a group in any app. If you are starting from receipts and who paid for what, the [who owes who calculator](https://www.evenoutapp.com/tools/who-owes-who-calculator) does that first step.

## How does the calculator find the fewest payments?

Three steps, all in whole cents:

1. **Net balance for each person.** Add up the IOUs owed to them and subtract the IOUs they owe. Positive means they are owed money, negative means they owe it, and the four nets add up to 0.
2. **Cancel exact pairs.** If one person's net debt is exactly what another person is owed, those two settle with a single payment and drop out.
3. **Match biggest to biggest.** The person who owes the most pays the person who is owed the most, using the smaller of the two amounts. Repeat until every net is 0.

## Worked example: six IOUs among four people

The calculator opens with six IOUs that add up to $175:

- A owes B $20
- D owes B $40
- C owes D $55
- B owes C $15
- C owes A $10
- A owes D $35

Paying each one on its own takes 6 payments. Adding up each person's side gives the nets:

| Person | Owes in total | Is owed in total | Net balance |
|---|---|---|---|
| A | $55 | $10 | Owes $45 |
| B | $15 | $60 | Is owed $45 |
| C | $65 | $15 | Owes $50 |
| D | $40 | $90 | Is owed $50 |

A owes exactly what B is owed, and C owes exactly what D is owed, so two pairs cancel. A pays B $45 and C pays D $50. That is 2 payments worth $95 instead of 6 worth $175.

## What happens when no pair cancels?

Say the nets are A owes $50, B owes $30, C is owed $45 and D is owed $35. No debt matches any credit, so the biggest debtor goes first. A pays C $45, B pays D $30, and A pays D the last $5. That is 3 payments, the most four people ever need. To try it, enter A owes C $45, A owes D $5 and B owes D $30, and set the other three amounts to 0.

A different set of 3 payments reaches the same result: A pays D $35 and C $15, and B pays C $30. An app can therefore show different payments than this page does. Each person's net cannot differ.

## Why does the calculator stop at four people?

The fewest payments for a group is the number of people with a nonzero net, minus the most separate subgroups you can form that each add up to zero on their own. Four people with nonzero nets can only divide into two pairs, which need 2 payments, or stay one group, which needs 3. Two pairs happen exactly when one debtor owes what a creditor is owed, which is the exact pair step, so nothing can beat the rule. With more people, subgroups of three or more can settle among themselves, and finding them takes a search this calculator does not do.

## Common mistakes

- **Putting the same person on both sides.** An IOU from A to A is not a debt. The calculator warns and shows no result until you change a number.
- **Entering an IOU that was partly paid.** Enter only what is still owed. If A owes B $20 and has paid $10, enter $10.

## How this works in EvenOut

In an EvenOut group the same idea is a setting. "Simplify debts" sits under "Settling up" in group settings, tagged "Recommended", and it is on by default: "Fewer payments, same totals." The "Balances" block lists your balance with each person rather than the whole group's, so the calculator is where you see all four nets side by side.

The reasoning behind each step is in [how simplify debts works](https://www.evenoutapp.com/guides/how-simplify-debts-works). [The minimum number of payments to settle debts](https://www.evenoutapp.com/guides/minimum-transactions-to-settle-debts) covers how low the count can go, and [apps that simplify debts](https://www.evenoutapp.com/alternatives/apps-that-simplify-debts) lists which apps offer it.

## Frequently asked questions

### Is this the fewest payments in every case?

For up to four people, yes, because the only way to do better than one group is two separate pairs, and the exact pair step already finds those. With six people it can miss. Nets of +$30, +$10, +$10, minus $15, minus $15 and minus $20 settle in 4 payments as two groups of three, and this rule makes 5.

### What if two people owe each other?

Enter both IOUs. If A owes B $30 and B owes A $20, A's net is minus $10 and B's is plus $10, so the two IOUs become one payment of $10 from A to B. The amounts that run in opposite directions net out before any payment is chosen.

### Can I use it for more than four people?

Not this one, which has four slots. The who owes who calculator takes up to six people and starts from what each person paid. An EvenOut group holds up to 200 people, and its Simplify debts setting works across the whole group.

### Can I enter IOUs in different currencies?

Keep every IOU in one currency, because the calculator adds amounts without converting. As of October 2026, Splitwise says Simplify Debts "works within each currency separately" and does not convert. EvenOut does not convert currencies either, and it keeps simplify debts per currency.

### Will the payments match what my app shows?

Not always, because more than one set of payments can clear the same nets. As of October 2026, Splitwise says it re-runs the arrangement whenever an expense or payment is added, so the payments it shows can change as the group adds entries while no one's total balance does.

## Sources

- Splitwise: What is Simplify Debts?