How is the weighted rent share calculated?

Each room starts with its square footage as a base score. Amenity bonuses are added as percentages of that base: private bathroom adds 15%, large closet adds 5%, and great natural light adds 5%. Each room's final score is divided by the sum of all scores to get its percentage, then multiplied by total rent.

What if two rooms are the same size?

If all inputs are identical — same sq ft and same amenities — the split becomes perfectly equal. The equal-split toggle is also available if you prefer to bypass weighted calculation entirely.

Should shared spaces like the living room be included in sq ft?

No. Enter only each person's private bedroom square footage. Shared spaces are implicitly covered by the equal portion of the weighting. If one roommate has exclusive use of a den or office, you can add those square feet to their room size.

What does the equal-split toggle do?

It divides total rent evenly among all roommates regardless of room details. You can flip between weighted and equal split to compare the difference.

How many roommates does this support?

The calculator supports 2 to 8 roommates. You can add or remove rows dynamically.

Is my data saved anywhere?

No. All calculations run entirely in your browser. Nothing is sent to a server and nothing is stored after you close the tab.

Rent Split by Room Calculator

Enter total rent and each roommate's room details to calculate a fair, weighted rent split based on size and amenities.

Rent Details

Total Monthly Rent

Equal split (divide evenly)

Rooms

Enter rent and room details, then click Calculate Split.

Weighted by room

Detailed Breakdown

Room	Sq ft	Score	Share	Rent
Total			100%	$0.00

Amenity Weights Applied

Private bathroom +15% Large closet +5% Great natural light +5%

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Summary

This calculator distributes total rent among roommates proportionally, weighting each room by its square footage and optional amenity bonuses — private bathroom, closet size, and natural light. Enter the monthly rent, add each roommate's room details, and the tool instantly shows how much each person owes. You can also override any share with an equal-split toggle.

How it works

Enter the total monthly rent at the top.
Add a row for each roommate and fill in their room's square footage.
Optionally check amenity bonuses: private bathroom (+15%), large closet (+5%), great natural light (+5%).
The calculator assigns each room a weighted score and converts it into a percentage of total rent.
Switch to Equal Split at any time to divide rent evenly and compare.
Copy the final breakdown to share with your roommates.

Use cases

Dividing rent fairly when rooms are noticeably different sizes.
Justifying a higher share for a room with a private en-suite bathroom.
Settling roommate disagreements about who pays what before signing a lease.
Quickly recalculating shares when a new roommate moves in or rent increases.
Comparing equal-split vs. weighted-split scenarios side by side.
Sending a clean summary to all roommates via copy-to-clipboard.

Frequently Asked Questions

Last updated: 2026-05-28 · Reviewed by Nham Vu