Stop guessing who owes what. Enter your rooms, your people, and your bills. The planner weights each share by room size, occupancy, and usage, then shows the math so nobody feels ripped off.
You can save your apartment setup in this browser and reload it next month.
This table shows what happens if you split the bill equally versus using room size, occupancy, and usage. The difference is often bigger than people expect.
| Person | Equal share | Adjusted share | Difference |
|---|
Splitting a bill five ways sounds simple. It stops being simple when one person is gone for two weeks, another runs a space heater all winter, and the third bedroom is half the size of the others. A flat split hides those differences and causes arguments.
This planner uses three signals: room size (larger rooms usually cost more to heat and cool), occupancy (you should not pay for days you were not there), and usage (some people genuinely use more power or water).
Scenario 1. Four people rent a 3-bedroom. One person moves in on the 15th. Their share should be roughly half of a normal month. Set their start date and the planner handles the rest.
Scenario 2. One roommate works from home and runs a desktop, two monitors, and a mini-fridge. Their usage factor should be above 1.0, maybe 1.2 or 1.3 depending on the season.
Scenario 3. Two roommates share a large master bedroom. They can split that room's weight between them, or one can pay a little more if they take the closet side.
This planner assumes one bill covers the whole unit. If your building already meters each room separately, you probably do not need a split. Usage factors are estimates. If you want real numbers, pick up a smart plug energy monitor and measure each person's devices for one week.
The planner also assumes shared spaces (kitchen, bathroom, hallway) are split evenly by the number of occupants. It does not try to guess how many hours each person spends cooking or showering.
Set their occupancy start date to the 10th. The planner counts only the days they lived there that month.
No. Only count private rooms. Shared spaces are split evenly.
Anything that makes one person use more than average. Working from home, gaming rigs, space heaters, or a mini-fridge in the bedroom are common examples.
If each unit already has its own meter, you probably do not need a split planner. This works best when one bill covers the whole unit.
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Last updated: April 2026 · Version 1.1 · Fair Split is a standalone project. Find more at hub2.day.