Share a bill by what each person ordered or by shares, with tax and tip shared in proportion.
In By items mode, type the bill before tax and tip, then the amount of each person's own items; a blank box counts as 0. Whatever nobody claimed, the shared remainder, is split equally between all people, so shared starters or a bottle of wine need no special entry. The page opens on a bill of 100 with 8% tax and 15% tip for three people with items of 40, 25 and 15. The remainder is 20, 6.67 each, so the parts are about 46.67, 31.67 and 21.67. If the items add up to more than the bill, a message appears under the bill box.
In By shares mode each person has a weight, 1 by default. A person with 2 shares pays twice the part of a person with 1. On a bill of 50 split between shares of 2 and 3 the parts are 20.00 and 30.00. Shares can be 0 for someone who pays nothing, but at least one must be above 0. There is no shared remainder in this mode, because the whole bill is divided by weight. For an equal split with a tip, the tip-calculator is simpler.
Tax and tip are percentages of the bill before tax. Each person pays their part × (1 + (tax % + tip %) ÷ 100), so someone with a bigger part pays a bigger part of the tax and the tip. In the opening example, 46.67 × 1.23 gives Ana 57.40, Ben 38.95 and Cy 26.65, which add up to 123.00: 100 bill, 8.00 tax and 15.00 tip. Leave tax and tip empty for none. Names are optional; an empty name shows as Person 1, Person 2 and so on.
Amounts are whole cents shared by the largest-remainder method, in the items column and the tax and tip column: each person gets their amount rounded down, then the leftover cents go to whoever had the biggest fraction, the earlier person on a tie. Every column adds up exactly and no amount is negative. Splitting 100.00 three ways by equal shares gives 33.34, 33.33 and 33.33. The Check tile adds the totals again and compares them with bill + tax + tip. Amounts have no currency symbol. This is an estimate, not financial advice.
Choose By items and type each person's own items. Anything left over is split equally, and tax and tip follow each person's part. With 40, 25 and 15 on a 100 bill, the 20 remainder adds 6.67 to each part.
In proportion to each person's part of the bill, not equally. At 15% on a bill of 100, someone whose part is 46.67 pays 7.00 of tip, and someone whose part is 21.67 pays 3.25.
The leftover cents go to the people with the biggest fractions, the earlier person on a tie. Three equal shares of 100.00 give 33.34, 33.33 and 33.33, so the totals add up exactly to 100.00. The Check tile says so.
For splits that are not by item, such as 2 shares for a couple and 1 for a single person. Each person pays bill × their shares ÷ all shares, plus their proportion of tax and tip.
The amounts typed for each person add up to more than the bill total. Check the bill, or switch to By shares.