Who owes who, in the fewest payments.
A free cost-split calculator for group trips. Add who paid for what, and it works out the fewest payments that square everyone up.
Split calculator
3 payments square everyone.
Total · 04 heads
£688.50
Avg per head£172.13
Costs04
- Dee pays Ana £180.12
- Ben pays Ana £52.25
- Ben pays Cal £31.88
The fewest payments that clear every balance. It can pair two people who never shared a cost; everyone still ends up square.
// Heads · 04
Paid · netPaid £412.50Share £180.13
Owed+£232.37
Paid £96.00Share £180.13
Owes−£84.13
Paid £180.00Share £148.12
Owed+£31.88
Paid £0.00Share £180.12
Owes−£180.12
// What was spent · 04
Split 4 ways · £103.13 each
Split 4 ways · £34.00 each
Split 3 ways · £32.00 each
Split 4 ways · £11.00 each
01 The answer, at the top
How many payments square everyone, worked out again as you type, with the count pinned in view.
02 People and costs, below the answer
Scroll the screen to add who’s in and what was spent. Untick anyone a cost wasn’t for and it splits between the rest.
03 One link, at the bottom
Send it to the group chat. The whole split rides inside the link, so we never store a thing.
- Price
- Free
- Account
- None
- Stored
- Nothing
Fewest payments, or pair by pair
Both answers leave everyone square to the penny. They differ in who pays whom.
Pair by pair settles what each two people owe each other, so every payment traces back to costs they shared. In the example, Dee pays Ben £32.00: Dee’s share of the dinner Ben paid for. That is how the ledger in the Truce app settles.
Fewest payments adds up everyone’s balance first and routes the money the shortest way. Dee pays Ana once, £180.12, which also covers what Dee owes Ben and Cal. That is 3 payments instead of 6, at the price of some that don’t trace to anything those two shared.
Fewest payments · 03
- Dee pays Ana£180.12
- Ben pays Ana£52.25
- Ben pays Cal£31.88
Pair by pair · 06
- Dee pays Ana£103.12
- Ben pays Ana£71.13
- Cal pays Ana£58.12
- Ben pays Cal£45.00
- Dee pays Cal£45.00
- Dee pays Ben£32.00
How the sum is done
Six rules, and no judgement calls. The netting is the same code the Truce app’s ledger runs, checked against the app’s own copy every time either one changes.
Each cost splits evenly
A cost divides between the people ticked for it. When it won’t divide exactly, the spare pennies go one each to the first people on the list, so £100 three ways is £33.34, £33.33 and £33.33.
To the penny
Nobody owes themselves
Whoever paid is owed by everyone else the cost was for. Their own share stays with them.
Payer excluded
Balances add up to zero
Everyone’s balance is what they paid minus their share. Across the group they add up to exactly nothing, which is how you know no money has gone missing.
Always
Fewest payments
The person who owes the most pays the person owed the most, as much as either can take, then the next pair, until everyone is square. A group of n people never needs more than n − 1 payments.
Biggest first
Pair by pair
What two people owe each other cancels out first, so each pair ends with one payment in one direction, or none.
Netted
One currency per split
Everything is in the currency you pick. Convert anything paid in another before you type it in.
No conversion
A calculator, or a ledger that keeps itself
This page works out one split, once, from what someone remembers to type in. In Truce the same ledger runs for the whole trip, filled in as people book.
- Who adds the costs
- This page · One of you, afterwards, from the receipts.
- In Truce · Whoever books something. It lands on the ledger as they do.
- An uneven cost
- This page · Enter it as two costs.
- In Truce · A custom amount for each person, or mark that everyone paid at the venue.
- Other currencies
- This page · Convert by hand before you type.
- In Truce · Enter each cost in the currency it was paid in. It converts at the rate you set, or a live rate on Pro trips.
- Someone joins late
- This page · Re-tick who each cost was for.
- In Truce · A split freezes when the cost is booked, so a late joiner never re-splits what was already agreed.
- Settling up
- This page · Send the link and pay each other.
- In Truce · Record each payment, nudge whoever hasn’t, and watch the balances clear on everyone’s phone.
Questions
Is the calculator free, and do I need an account?
It’s free, with no account and nothing to install. It runs in your browser: open the page and start typing.
Where does what I type go?
Nowhere. The sums happen on your device, and nothing you type is sent to Truce or anyone else. When you copy a link, the split is written into the link itself, after the #, which is the part of a web address browsers never send to a server. Anyone with the link can read it, so share it where you would share the numbers.
Why would someone pay a person who never paid for them?
That’s the fewest-payments answer doing its job. It only cares that everyone ends up square, so it routes money the shortest way, even between two people who never shared a cost. Switch to pair by pair if you would rather every payment traced back to something those two shared. Everyone ends up square either way.
Can I split one cost unevenly?
Not on this page: each cost splits evenly between the people ticked for it. Enter an uneven cost as two instead, say the room everyone shared and the upgrade one person had, ticked for just them. The Truce app takes a custom amount for each person.
We paid in more than one currency. What now?
Pick one currency for the split and convert anything paid in another before you type it in. In the Truce app, each cost can be entered in the currency it was paid in and converted for you.
Someone remembered a cost after we shared the link.
Open the link, add the cost and send the new link. The old one still shows the old numbers, so make sure everyone uses the new one.
Never do this sum again.
Truce is a group trip planner for iPhone. The group votes on what to do, the winners land on a shared plan, and costs go on one ledger as people book them, netted the same way and live on everyone’s phone all trip.
Free. Open it on your iPhone - it installs through TestFlight, Apple’s app for testing new apps.