Do I need an account to use the calculator?

No. It works right on this page, it doesn't save anything and needs no account.

How are transfers kept to a minimum?

Those who owe and those who are owed are sorted from the largest difference down and matched: each transfer fully settles one of the two. With N people, N − 1 transfers or fewer are enough.

What if we are many, or the trip lasts several days?

That's what an app is for: in Busimy everyone adds what they pay from their phone and everyone's balance updates on its own.

Split bill calculator: who owes whom

To split expenses between friends, add up everything that was paid, divide by the number of people and subtract from each one what they already paid: whoever paid too much gets money back, whoever paid too little pays. This calculator does the math and tells you who pays whom, with the fewest transfers.

How the math works

Add up everything the group paid.
Divide it by the number of people: that's each one's share.
Subtract from each one what they already paid. If it's positive, they're owed; if negative, they owe.
Those who owe pay those who are owed, starting with the biggest differences. That settles everything with few transfers.

An example with numbers

A barbecue for four: Anna paid for the meat ($96), Ben the drinks ($40), Carla the charcoal and bread ($24) and Dan paid nothing. Total: $160, so $40 each.

Anna paid $56 too much, Ben is even, Carla owes $16 and Dan $40. Two transfers settle it: Dan sends Anna $40 and Carla sends Anna $16.

When it isn't split equally

If a couple counts as two, or someone only joined for dessert, use the Shares column: each one pays by their shares. With Anna 2, Ben 1 and Carla 1, out of $160 Anna pays $80 and the other two $40 each.

If each expense is split differently (someone doesn't eat meat, another didn't drink), in Busimy you create an event, invite the group and each expense is split among those who took part: the app keeps everyone's balance and updates it with every payment.

Frequently asked questions

Do I need an account to use the calculator?: No. It works right on this page, it doesn't save anything and needs no account.
How are transfers kept to a minimum?: Those who owe and those who are owed are sorted from the largest difference down and matched: each transfer fully settles one of the two. With N people, N − 1 transfers or fewer are enough.
What if we are many, or the trip lasts several days?: That's what an app is for: in Busimy everyone adds what they pay from their phone and everyone's balance updates on its own.