How it works
How this tool works.
Splitting rent evenly is easy until the rooms aren’t even. When one roommate gets the big room with the closet and another gets the converted den, a flat split starts to feel unfair — and “feels unfair” is how roommate arrangements fall apart. A square-footage split is the simplest objective alternative: each person pays in proportion to the private space they actually get.
This calculator does both. Enter the total rent, then either pick the number of roommates for an even split, or list each bedroom with its square footage and let the tool weight the shares. The output is arithmetic on the numbers you enter — a starting point for the conversation, not a ruling on what’s fair in your household.
Enter the total monthly rent for the whole apartment or house.
Choose a method: an equal split across a number of roommates, or a split weighted by room size.
For the room-size method, add a row per bedroom with its square footage — shared spaces like the kitchen and living room are treated as common and left out.
The tool shows each person’s share: rent ÷ people for the even split, or rent × (room sq ft ÷ total bedroom sq ft) for the weighted one.
Make the result useful
Roommate rent-split agreement
Total rent is the full recurring amount due under the lease.
Split method is equal or proportional to the room measure selected.
Room sizes describe private rooms, not necessarily shared-space value.
The calculated share is an agreement aid, not a change to lease liability.
The assumptions that move this result
Total rent
Full recurring rent.
Method
Equal or size-proportional split.
Room sizes
Private-room area used for weighting.
Roommates
People included in the split.
equal share = total rent ÷ roommates; size share = total rent × room size ÷ total room sizes
Use the output as a documented scenario result, not a guarantee.
Read the number in context
Worked scenario
Scenario: $2,400 split equally by two is $1,200 each.
Edge case
Edge case: unequal amenities can justify a negotiated method beyond square feet.
Does not alter joint-and-several lease obligations.
Before you act
• Agree method before move-in.
• Write shares down.
• Confirm lease payment responsibility.
Worked formula
equal share = total rent ÷ roommates; size share = total rent × room size ÷ total room sizes
Is this a forecast?
No. It calculates the assumptions you enter.
Can it replace professional review?
No. Use current records and qualified advice.
What should I save?
Keep the assumptions and source records used for the decision.