Rent Split Calculator
A fair split of the rent between housemates, by room size or by income.
Good to know. The biggest room usually goes to whoever brings it up first. A number settles it more kindly.
How it works
In plain words
By size: the shared-space part of the rent is split equally, and the rest in proportion to bedroom size. By income: each person pays their share of the household’s total income.
The formula
by size: pay = rent × shared% ÷ people + rent × (1 − shared%) × room ÷ all rooms by income: pay = rent × income ÷ total income
Worked example
40% of 3,000 is 1,200 for shared space, 400 each. The other 1,800 goes by bedroom size: Anna’s 14 of 36 m² is 700, so Anna pays 1,100.00, Ben 900 and Chris 1,000.
Sources
No outside data or rates: this is plain arithmetic.
4 automated tests check its answers on every change.
About the rent split calculator
Splitting rent equally is simple, but it rarely feels fair when one bedroom is twice the size of another or has its own bathroom. This calculator splits the rent in a way everyone can check, so the conversation is about the method, not about who gets the good room.
By room size, part of the rent covers the space everyone shares, such as the kitchen, living room and hallway, and that part is split equally. The rest is split in proportion to bedroom size, in square metres or square feet. 30 to 50% for shared space is typical; the bigger the shared rooms, the higher it should be. Adjust for extras by adding to the room size: an en-suite bathroom or a balcony is worth a few square metres.
By income suits couples and families, where each person pays the same share of what they earn. Someone earning 60% of the household income pays 60% of the rent.
Utilities, internet and cleaning supplies are usually split equally, whatever method you use for rent. Write the agreement down, and check it again when someone moves out or the rent goes up.
Questions people ask
How do you split rent fairly by room size?
Split a share of the rent for common areas equally, often 40%, and the rest in proportion to each bedroom’s size.
Should couples split rent 50/50 or by income?
Either can be fair. Splitting by income means each pays the same share of what they earn, which leaves both with the same share for everything else.
How much more should the master bedroom pay?
In proportion to its size, plus a bit for extras like its own bathroom. Adding a few square metres to its size is an easy way to count them.