Splitting rent with roommates is where a lot of shared-flat friction starts, because splitting it equally is only fair when the rooms are equal, and they rarely are. This free calculator splits the rent by room size, adds a premium for a private bathroom, can weight by income instead, and splits your shared utilities too, so everyone sees a number they agree is fair. It works in any currency.
TL;DR: Enter the total rent, add each roommate with their room size (or income), tick anyone with a private bathroom and set a premium, and add your monthly utilities. The calculator shows each person’s fair monthly share, rent plus an equal split of utilities, updating live.
Enter the rent, add each roommate, choose how to split, and add utilities. Shares update live.
This is a template calculation, not legal or financial advice. How you split rent between yourselves is separate from the lease, which usually makes each roommate responsible for the whole rent. Utilities are split equally because everyone uses them.
How to split rent so it actually feels fair
Splitting rent equally is the default, but it is only fair when the bedrooms are the same. Most shared flats are not like that: one room is bigger, one has an attached bathroom, one gets the balcony. A fair split accounts for those differences instead of pretending they do not exist.
- Start with room size. Give each person a share of the rent equal to their bedroom’s share of the total private-bedroom area. Shared spaces, the living room, kitchen, and hallways, are common to everyone and are already inside the rent. This handles the single biggest difference, a large master versus a small second bedroom.
- Add a premium for a private bathroom. An en-suite is worth more than its floor area alone, so tick that room’s private-bathroom box and set a premium, usually 10 to 20 percent. The calculator raises that person’s share and lowers everyone else’s by the same total, so the numbers still add up to the full rent.
- Split utilities equally. Electricity, water, internet, and gas are used by everyone, so they are almost always split equally rather than by room size. Enter your monthly utilities and the calculator adds an equal utilities share to each person on top of their rent share.
- Or split by income. If you would rather the rent sit proportional to what each person earns, switch the method to income and enter each person’s monthly income. This is common between partners and close friends.
Put the split in writing
However you divide the rent, write it down: who pays what, when it is due, and how you will handle a month when someone is short. A one-page roommate agreement, signed by everyone, prevents most disputes. Remember that this split is between you; if you are all on one lease, the landlord can usually pursue any of you for the whole rent, so a fair split also means agreeing what happens if a housemate cannot pay.
This tool is general information, not legal or financial advice; leases and local rules vary, so confirm your obligations against your lease. Last reviewed July 2026.
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