Rent Split Calculator

Split monthly rent among 2–10 roommates equally, by agreed percentages or by bedroom area, with exact cent totals.

Individual Monthly Rent

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How to Use the Rent Split Calculator

Enter monthly rent in US dollars with up to two decimal places, choose the number of roommates and a method. Equal split needs no weights. Custom percentage requires one percentage per roommate totaling exactly 100%. Bedroom-area mode allocates the full rent in proportion to positive room areas measured in the same units. Calculate, verify the allocated total and copy the results if useful.

Formula and Explanation

Exact share = rent in cents × individual weight ÷ total weight
Floor each share, then distribute remaining cents by largest remainder.

Equal shares use identical weights. Percentage or room-area shares use rent × individual weight ÷ total weight. Allocation is performed in integer cents: floor each exact share, then award the remaining cents to the largest fractional remainders. Ties are resolved in roommate order. This ensures the displayed amounts sum to the entered rent.

No method here is legally required or objectively fairest. Agree with your roommates on a method and check your lease separately. Area mode allocates all rent by bedroom area; it does not separately value shared rooms, bathrooms or amenities. Percentages support up to four decimal places; room areas up to six. Utilities and other expenses are excluded unless you include them in the rent amount.

Worked Example

Splitting $1,000 among three roommates gives $333.34, $333.33 and $333.33. For a 50% / 30% / 20% agreement on $1,200, the amounts are $600, $360 and $240. Room areas of 100 and 150 sq ft divide $1,000 into $400 and $600.

Frequently Asked Questions

Why can equal shares differ by one cent?

Some rent totals cannot be divided into identical whole-cent amounts. The remaining cents are distributed deterministically in roommate order when all fractional remainders tie, so the total is still exact.

Must custom percentages equal 100%?

Yes. The calculator rejects a total above or below 100% rather than silently rescaling it. Each percentage must be non-negative; an agreed zero-percent share is allowed.

How does bedroom-area splitting work?

Each share equals the full rent multiplied by that bedroom’s area divided by total bedroom area. Use the same area units for everyone. Each area must be positive, and shared space is not priced separately.

Which rent split is fairest?

That depends on the household’s agreement, room sizes, amenities and other circumstances. This tool compares arithmetic methods and does not establish a legal obligation or a uniquely fair allocation.