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Rent split calculator by room size
The fairest rent split charges bigger rooms and rooms with extras like a private bathroom more, while everyone shares the common areas and utilities equally. Enter your rent, rooms and features below to get each flatmate's monthly amount.
Updated November 2026
Rent splitter
Electricity, water, internet, maintenance. Always split equally per person.
The part of the rent that pays for the kitchen, hall and other shared space. 0% means rent follows room size only.
How it works
- Equal divides the rent by the number of people. Use it when rooms are close in size and nobody has a private bathroom.
- By room size first takes the common-area share and splits it equally per person. The rest is split in proportion to each room's area, then divided among the people in that room.
- Room size + features works the same way, but each room's area is increased by the premiums you set. A 120 sq ft room with a private bathroom at 15% counts as 138 sq ft.
- Utilities are always split equally per person, whatever method you pick.
Amounts are rounded to the nearest cent or paisa, and any leftover cent goes to the person with the largest fraction, so the shares always add up to the exact rent.
Worked example: three flatmates, 30,000 rent
A three-bedroom flat costs 30,000 a month plus 3,000 in utilities. The rooms are 150, 120 and 100 sq ft. The 150 sq ft room has a private bathroom (15%), and the 120 sq ft room has a balcony (5%). The flatmates agree to keep 30% of the rent for common areas.
- Common share: 30% of 30,000 is 9,000, or 3,000 per person.
- Weighted room sizes: 150 × 1.15 = 172.5, 120 × 1.05 = 126, and 100. The total is 398.5.
- The remaining 21,000 is split by weight: 9,090.34, 6,639.90 and 5,269.76 (rounded).
- Add the 3,000 common share and 1,000 of utilities each.
| Room | Rent | Utilities | Total |
|---|---|---|---|
| 150 sq ft, private bath | 12,090.34 | 1,000 | 13,090.34 |
| 120 sq ft, balcony | 9,639.90 | 1,000 | 10,639.90 |
| 100 sq ft | 8,269.76 | 1,000 | 9,269.76 |
An even split would be 11,000 each. The person in the big room with the attached bathroom pays about 2,090 more, and the person in the smallest room saves about 1,730.
How to agree on a fair split
- Measure the rooms. Length times width is enough. Guessing leads to arguments later.
- Agree the premiums before choosing rooms. If you set the bathroom premium after someone has picked that room, it feels personal. Set the numbers, then let people choose.
- Do not skip the common-area share. With 0%, a 60 sq ft box room can end up paying very little while using the kitchen as much as anyone. 30 to 50% is a common middle ground.
- Write it down. Once you agree, put the rent as a monthly recurring expense in a shared group so nobody has to recalculate.
Frequently asked questions
What is the fairest way to split rent?
When rooms are about the same, split evenly. When they differ, split by room size and add a premium for features like a private bathroom or balcony. Keeping part of the rent for common areas split equally stops the person in the smallest room from paying almost nothing for the kitchen and living room.
What is the common-area share?
It is the percentage of rent that pays for spaces everyone uses, like the kitchen, hall and balcony. That part is split equally per person, and only the rest is split by room size. Many flatmates use 30 to 50 percent.
How much more should a room with a private bathroom pay?
There is no fixed rule. A premium of 10 to 20 percent on that room's weight is common. Check local listings: if rooms with an attached bathroom rent for 15 percent more nearby, use 15 percent.
How do couples sharing a room split rent?
Set People in room to 2. The room's rent is split between the two of them, and they each pay a full share of the common area and utilities, since they both use the kitchen, water and electricity.
Are utilities split by room size too?
No. Electricity, water, internet and maintenance depend on how many people live there, not on room size, so this calculator splits them equally per person.
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