Free tool
Partial participation expense calculator
A taxi for three, dinner for four, a rental for two. Enter the amount, tick who was involved: each of them gets an exact share and everyone else stays at zero.
Expense amount
Who takes part?
Untick anyone who did not take part in this expense: they pay nothing.
Total
€0
Participants
3
What each person owes
Enter the amounts to see the result.
Shares are equal between ticked people. When the amount does not divide evenly, the remaining cent or cents go to the first people on the list, so the shares always add up to the exact total.
Everything is computed in your browser: nothing is stored or sent.
Whole-cent arithmetic with a largest-remainder distribution of the leftovers: the shares are checked against the total by automated tests.
For tracking several expenses over time, with your friends.
Why this needs its own tool
In any group, most expenses do not involve everybody. Three people share a taxi, four go to dinner, only two rent equipment. Dividing everything by the full headcount creates small unfairnesses that add up over a trip until someone finally mentions them.
This calculator keeps the whole group on screen — which matters, so nobody gets forgotten — but only charges the people you tick. Everyone else shows as zero, which makes the split easy to read and easy to check.
How the cents are handled
The amount is converted to whole cents, divided by the number of ticked people, and the leftover cents are handed out one by one to the first ticked rows. On £121.35 split between four people, three pay £30.34 and one pays £30.33 — the total is exactly £121.35.
No floating-point rounding is involved, so you will never see a total of £121.36 or a share of £30.3375.
Across a whole trip
A single expense is easy to handle by hand. The trouble starts at thirty of them, each with its own list of participants: nobody wants to redo that sum on the last evening. In a Pivunio group you pick the participants expense by expense and the balances update themselves.
Frequently asked questions
Should I remove people who were not there?
No, just untick them. Leaving them visible at zero proves they were not accidentally left out, which prevents the classic "are you sure you counted me?" conversation at settle-up time.
What if someone only took part halfway?
This calculator is all-or-nothing. For a measured partial share — a half portion, a child, someone who left before dessert — use the shares and weights calculator, which accepts weights such as 0.5 or 1.5.
How many people can I add?
As many as a meal or a trip with friends needs. The tool runs entirely in your browser: nothing is sent or stored, and no account is required.
Editorial review — Written and reviewed by the Pivunio team. The methods described here are the ones the app itself uses, and they are covered by automated tests.