Room-Size Rent Splitter: Divide Rent by Bedroom Size Fairly
Bigger bedroom, bigger share. Enter the rent, set the shared-space portion, add each room’s size, and get each roommate’s exact share in seconds.
Roommates and bedroom sizes (sq ft or any consistent unit)
🔒 No signup. This calculator runs entirely in your browser — nothing you enter is sent to a server or stored anywhere.
How It Works
Enter the rent and common share
Type the full monthly rent and the percentage that covers shared space (kitchen, living room, bathrooms). 20% is a common default.
Add each bedroom’s size
Add a row per roommate and enter their bedroom size in square feet (or square meters — any consistent unit).
Split it fairly
The common portion is split equally; the rest is split by bedroom size. The bigger the room, the bigger the share.
Worked Example
Three roommates split $2,000 of rent with a 20% common-area share. That is $400 for shared space ($133.33 each) and $1,600 for private rooms, split by size across rooms of 200, 150, and 100 sq ft:
| Roommate | Room size | Common share | Private share | Total |
|---|---|---|---|---|
| Alex | 200 sq ft | $133.33 | $711.11 | $844.45 |
| Sam | 150 sq ft | $133.33 | $533.33 | $666.67 |
| Jo | 100 sq ft | $133.33 | $355.56 | $488.88 |
| Total | 450 sq ft | $400.00 | $1,600.00 | $2,000.00 |
Frequently Asked Questions
What size should I enter?
Your bedroom’s floor area in square feet or square meters. The unit does not matter as long as every room uses the same one.
What should the common-area percentage be?
Most groups use 15–25%. Agree on it first — it represents the shared kitchen, living room, and bathrooms everyone uses equally.
One room is much bigger — is that fair?
That is exactly what this split handles: the bigger-room roommate pays proportionally more of the private portion.
Is my data sent to a server?
No. The calculation runs entirely in your browser. Nothing you enter is uploaded, stored, or shared.
Related Calculators
- Rent Split Calculator — split rent equally or by custom amounts.
- Income-Proportional Split Calculator — split rent by income instead of room size.
- Utility Bill Splitter — split the shared utility bills.
- Split by Shares Calculator — split by custom shares like 2/1/1.