Fair Rent Split Calculator
Calculate a fair rent split among roommates by room size and amenities.
Each person pays proportionally to the space they use — no more awkward guessing.
Rent splitting between roommates can be done equally (simplest) or proportionally based on room size, amenities, or personal income. Different methods produce very different results, and it’s important to agree on the method before signing a lease.
Method 1 — Equal split: Each Person’s Share = Total Rent ÷ Number of Roommates
Method 2 — By room square footage: Person A’s Share = (Room A sq ft ÷ Total Living Space sq ft) × Total Rent
Method 3 — By income (ability-to-pay method): Person A’s Share = (Person A’s Income ÷ Total Combined Income) × Total Rent
Method 4 — Hybrid (room size + amenity premium): Add a fixed dollar premium for rooms with private bathrooms, better views, larger closets, etc., then split the remaining rent by room size.
Adjusted rent formula: Base Rent = Total Rent − All Premiums Person A’s Base Share = (Room A sq ft ÷ Total sq ft) × Base Rent Person A’s Total = Base Share + Applicable Premium
Where:
- Total Rent: the full monthly lease amount (not including utilities)
- Room sq ft: the area of each private bedroom only, or entire livable area if applicable
- Premium: a negotiated dollar amount for superior features (en-suite bath, parking, balcony access)
- Shared spaces: common areas (kitchen, living room, bathrooms) are typically excluded from the room-size calculation since everyone uses them equally
Reference: typical room premiums:
- Private en-suite bathroom: $50–$200/month premium
- Larger room (50%+ bigger): $100–$300/month premium
- Parking space: $50–$150/month
- Private balcony or patio: $50–$100/month
Worked example: 3-bedroom apartment, $2,400/month rent. Room sizes: 180 sq ft, 150 sq ft, 120 sq ft. Room 1 has a private bathroom (agree on $150 premium).
- Total room area = 180 + 150 + 120 = 450 sq ft
- Base rent after premium = $2,400 − $150 = $2,250
- Room 1 share = (180÷450) × $2,250 + $150 = $900 + $150 = $1,050
- Room 2 share = (150÷450) × $2,250 = $750
- Room 3 share = (120÷450) × $2,250 = $600
- Check: $1,050 + $750 + $600 = $2,400 ✓