Who owes who calculator — settle up in the fewest payments

Type in the IOUs you already have — she paid for the taxi, he covered dinner, someone got the tickets — and this works out the shortest list of payments that clears all of them. It also does something no other settle-up calculator we could find does: it checks whether that list really is the shortest one possible, and tells you when it isn't.

What it does with your IOUs

Three steps, and you can watch each one happen above.

1. It nets everyone off. Every IOU is added up into one signed position per person: you are owed this much, or you owe that much. Who each individual debt was originally with stops mattering the moment the totals are in — which is why a long chain of small debts usually collapses into a couple of payments.
2. It matches the biggest to the biggest. The person owed the most is paired with the person owing the most, that debt is cleared as far as it goes, and the pass repeats. This is the same procedure behind every "simplify debts" button, Dolio's included.
3. It checks the answer against the true minimum. Step two is a shortcut, not a guarantee. So the calculator also works out, by brute force, the smallest number of payments that exists for your balances — and if the shortcut missed it, you get the shorter list instead.

Nothing you type is sent anywhere or saved. The whole calculation runs in your browser, and there is no account to make.

Why "simplified" can still be one payment too many

Splitting the difference between everyone in the fewest possible payments is, mathematically, a hard problem — hard in the formal sense that no known method solves it quickly for large groups. So apps use the shortcut in step two, and it is a good one. But it is a shortcut, and the pages describing it rarely say so. Splitwise's help centre, for instance, says its feature "restructures who owes whom within a group to minimize the total number of payments needed for everyone to settle up" and states no limitation at all (retrieved 15 August 2026). The other settle-up calculators promise the same thing in the same words.

Here is a case where the shortcut is beaten. Five people finish a weekend: Ana is owed 40, Ben 30, Cara 20, while Dan owes 50 and Eve owes 40. Match biggest to biggest and you get four payments. But look closer — Ana's 40 and Eve's 40 cancel exactly, and Cara's 20 plus Ben's 30 exactly cover Dan's 50. Settle those two clusters separately and it takes three. You can load this exact case into the calculator with the second link at the top of it.

That applies to Dolio's own settle-up screen as well as everyone else's — it runs the same shortcut, and this calculator runs a line-for-line copy of it, checked against the live code. The workings are in how to settle group debts with the fewest payments.

You never need more payments than people, minus one

Whatever the tangle looks like, there is a ceiling. If six of you carry a balance, five payments always finish it, and usually fewer. The reason is short: every payment can be sized to zero out at least one person's position, and the final one zeroes the last two at once. So the count can only ever go down from there.

This is the number worth carrying around. If someone in the group is proposing nine transfers for a six-person trip, the arithmetic is wrong before you check any of it.

What this calculator will not do

• One currency at a time. If the trip mixed euros and forints, convert first — a settlement across two currencies is a different question with an exchange rate in the middle of it.
• It settles balances, it doesn't track spending. There's no itemising, no receipts, no shares by percentage. It takes finished IOUs and tells you how to clear them.
• Above twelve people with a balance, it stops proving minimality. It still gives you a correct settlement; it just stops claiming that no shorter one exists, because at that size finding the proof is genuinely slow.
• Couples count as two people here. In a real group, two people sharing a wallet can be netted together first, which often removes another payment — that needs a group that knows they're a couple, which is an app's job, not a form's.

Keeping it going in Dolio

A calculator is the right tool once, at the end. If the same group keeps spending — a longer trip, a flatshare, a season of dinners — the useful thing is a running total instead of a reconstruction from memory. Dolio keeps the ledger as you go and settles it the same way this page does, and you can add people to a group as placeholder participants who never have to download anything or make an account. It's free to use and shows no ads.