Split an amount into parts

Dividing money so the cents add up

Splitting an amount sounds simple until cents get involved. Divide 100 into three and each part is 33.333…, but nobody can pay a third of a cent. Round each part to 33.33 and the three add up to 99.99: one cent has vanished. Round up and you have created a cent that did not exist. In accounts, invoices and payments, that missing or extra cent is a real problem. This tool divides the amount so that the parts always add up to the total exactly.

How the cents are shared out

The method is called the largest remainder method. Each part is first rounded down to a whole number of cents. The cents left over from that rounding are then given, one each, to the parts that were closest to the next cent up. For 100 in three parts, the result is 33.34, 33.33 and 33.33. The differences are never more than a cent and the total is exact.

Equal parts or proportional parts

• Equal parts: the amount is divided into the number of parts you choose, up to 500.
• Shares: give the weight of each part as numbers separated by commas. Shares of 3, 2 and 1 mean one half, one third and one sixth. You can also enter percentages such as 50, 30 and 20. They do not have to add up to 100, since the tool works with proportions.

Typical uses

Splitting the cost of a shared expense among people who use different amounts, distributing a bonus or profit among partners with different stakes, dividing an inheritance or a joint purchase, allocating an invoice to several departments, or sharing a bill unequally. The list of amounts can be copied and pasted into a spreadsheet.

What it does not do

The tool works with two decimals, which is the norm for most currencies, and does not apply rounding rules specific to a legal or accounting context. It does not check that shares are fair or that percentages add up to 100. For an equal split of a restaurant bill with a tip, the split the bill calculator is more direct.