Free tool
Split an expense by shares
Assign a number of shares to each person: the tool works out the value of one share and everyone's exact contribution.
The expense to split
Shares assigned
Whole number of shares. For example 2 per adult and 1 per child, or 3 / 2 / 1 depending on usage.
Total
€0
What everyone owes
Enter the amounts to see the split.
One share is worth the total divided by the sum of shares. Leftover cents go to the shares hit hardest by rounding.
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.
Thinking in shares
Shares are the most intuitive key when people do not weigh the same in an expense: two adults and two children on a meal, three households including one couple on a rental, heavy versus occasional use of a subscription.
Instead of computing percentages you assign a number: 2 shares, 1 share, and half a share simply becomes 1 against 2. The sum of shares then sets what one share is worth.
Pick a simple scale
The tool takes whole numbers, which covers every everyday case: if you want half shares, double the whole scale. "1.5 / 1 / 1" becomes "3 / 2 / 2" and gives exactly the same result.
Avoid over-fine scales: past a dozen levels nobody remembers the rule, and the difference in contribution becomes invisible in the final amount.
Compared with an equal split
An equal split is just a special case of shares: everyone gets one. Weights become worthwhile as soon as a difference in usage is obvious and accepted by the group. If nobody can justify the weighting, go back to an equal split — a simple rule beats a contested one.
Frequently asked questions
Can I use half shares?
Indirectly: multiply every value by two. A 1.5 / 1 scale becomes 3 / 2, with an identical result to the cent.
How do I handle someone who was absent?
Give them zero shares: they take no part in this expense. If attendance varies expense by expense, a Pivunio group suits better than a one-off calculation.
Is the total always exact?
Yes. The contributions always add up to exactly the amount entered, including when the division does not come out evenly.
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.