For reference only; enter this person's assigned area above.
Roommate Rent Split Calculator
Split monthly rent between roommates equally, by income, bedroom size and shared space, or custom weights. Compare monthly and annual shares and keep rounded totals exact.
Last updated: August 2026
Rent split result
Per-roommate rent split
| Roommate | Method-specific input | Percentage of rent | Monthly share | Annual share | Difference from equal split |
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Equal split comparison
The current method is compared with an equal split using the same monthly rent and active roommates.
| Roommate | Equal split | Selected method | Difference |
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How does equal rent splitting work?
Equal splitting divides the entered monthly rent by the number of active roommate rows. Every person receives the same percentage and monthly amount. Remove rows that should not be part of the household count.
How does income-proportional rent work?
Income proportionality divides rent according to each roommate's entered monthly income. A roommate with zero income receives a zero share, but at least one income must be positive. This is a budgeting method, not a required legal rule.
How does the bedroom-size method work?
Enter total home area and each paying person's assigned private bedroom area. The calculator subtracts private areas from the home area, divides the remaining common area equally, and adds each person's private and common allocations into chargeable area. If two people share a bedroom, each person can enter an equal fraction of that bedroom's area.
How do custom weights work?
Custom weights are relative numbers such as 1, 1, 1 or 1.2, 1, 0.8. They do not need to add to 100; the calculator normalizes them into percentages before allocating rent.
Why can rounded shares differ by one cent?
Some splits produce fractional cents. The calculator floors each raw share in the currency's smallest display unit, then gives remaining units to the largest fractional remainders in stable roommate-row order. This keeps displayed monthly shares equal to the entered rent instead of rounding each row independently.
Frequently asked questions
How should roommates split rent fairly?
Choose the method that matches the agreement you want to model: equal, income proportional, bedroom size plus equal common space, or custom weights. No single method is universally fairest for every household.
How should couples or shared bedrooms be handled?
Use one row for each paying person. For a shared bedroom, enter each person's assigned fraction of the bedroom area, and optionally note how many people share it.
How should unequal room sizes affect rent?
The bedroom-size method charges each person's entered private area and distributes the remaining common area equally. It does not decide which private-area measurement is appropriate.
Is income-proportional rent required?
No. It is a budgeting method that lets roommates compare contributions relative to entered incomes, not a universal requirement.
Why are rounding differences sometimes visible?
A rent total may not divide into whole cents or whole currency units. Largest-remainder rounding assigns the unavoidable extra unit while preserving the exact displayed total.
Are utilities included?
No. This tool is limited to recurring monthly rent. Utilities and other shared costs should be handled separately.
Privacy and scope
All calculations stay in your browser. Names, incomes, rent, areas, weights, and results are not sent to analytics and are not automatically saved. This calculator does not interpret leases, provide landlord or tenant legal advice, or split utilities and move-in costs.