Free tool
Rent Split Calculator
Work out who pays what in seconds. Split rent evenly, by room size or by income. No sign-up, no spreadsheet.
- Flatmate 1$266.66/wk33%
- Flatmate 2$266.67/wk33%
- Flatmate 3$266.67/wk33%
Nothing you type here is saved or sent anywhere. It all runs in your browser.
Three fair ways to split rent
Which method is fair for your house?
Split rent evenly
The simplest method, and the right one when the rooms are roughly the same and everyone earns enough that fairness is not in question. Total rent divided by the number of flatmates. It works because it is predictable and nobody has to justify their number.
Split rent by room size
The most common fairness adjustment in share houses. Whoever has the big room with the ensuite pays more, the person in the box room pays less. Weight each share by floor area (or a rough small / medium / large rating) and the calculator does the proportions. Shared spaces like the kitchen and living room are already baked into the total, so you only need to compare the private rooms.
Split rent by income
Less common, but some households prefer it when incomes are very different, for example a full-time earner sharing with a student. Each person pays in proportion to their take-home pay, so the rent takes a similar bite out of everyone. It is a values call for the house, not a default. Agree on it together before you move in.
Common questions
Splitting rent, answered
How should you split rent fairly between flatmates?
There are three common methods: split evenly, split by room size, or split by income. Even splits suit houses where the rooms are similar. Splitting by room size is the usual fairness adjustment when one room is clearly bigger or has an ensuite. Splitting by income is a values choice some houses make when earnings are very different. Agree the method before anyone moves in.
Should rent be split by room size?
If the rooms are noticeably different, yes. The person with the large room or the ensuite generally pays more, and the person in the smallest room pays less. You can weight by floor area in square metres, or just rate each room small, medium or large. Shared areas are already covered by the total rent, so you only compare the private rooms.
Is it fair to split rent based on income?
It can be, but it is optional and it only works if everyone agrees to it openly. Splitting by income means each person pays the same proportion of their take-home pay, so the rent hurts everyone equally. It suits households with big income gaps, like a working professional sharing with a student. It is not a default, so talk it through first.
Do you include the living room and kitchen when splitting rent?
No. Shared spaces are part of what everyone is paying for, so they are already included in the total rent. When you adjust for room size you only compare the private bedrooms. Everyone is effectively paying an equal share of the common areas on top of their room.
How do you split rent when one flatmate moves in partway through?
Work out their share with the calculator, then pro-rate it for the number of nights they are actually in the house that period. A flatmate who joins halfway through the month pays roughly half their normal share for that first month, then the full amount after. Flatmate Flow handles this kind of mid-period change automatically once the house is set up.
Rent sorted? Now do
the rest of the house.
Flatmate Flow splits every bill, rotates the chores and tracks the shared shopping. Set it up once and stop being the household nag.
It's free. No credit card. Nothing to cancel.