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Rent Split Calculator: Divide Rent Fairly Between Roommates

Enter the rent and each bedroom's size to get a split everyone can see is fair. Shared space is split equally per person, bedrooms are paid for by size, and you can add a premium for a private bathroom or set a room for a couple.

By Suman Sharma · Updated

Rent split · by room sizeLocal
$
  1. ft²

    $952.87 · 39.7% of rent

  2. ft²

    $760.25 · 31.7% of rent

  3. ft²

    $686.88 · 28.6% of rent

40%

Split equally per person. The rest is split by room size.

+15%

Counts that room as this much bigger.

Split adds up to
$2,400.00

How to use this tool

  1. Enter the rent and rooms

    Type the total monthly rent, then each bedroom's floor area in ft² or m². Add up to eight rooms.

  2. Mark couples and private bathrooms

    Set a room to Couple if two people share it, and switch on Private bathroom for an en-suite room.

  3. Agree the shared-space share

    Move the slider for how much of the rent covers the kitchen, living room and other shared space. Copy the split to send to the group.

Example

$2,400 rent, three bedrooms, one with its own bathroom.

Input

  • Room A: 150 ft², private bathroom
  • Room B: 120 ft²
  • Room C: 100 ft²
  • Shared space: 40% · Private bathroom premium: +15%

Result

  • Room A: $952.87 (39.7%)
  • Room B: $760.25 (31.7%)
  • Room C: $686.88 (28.6%)
  • Total: exactly $2,400.00

An equal split would be $800 each, so the person in the smallest room would be paying about $113 a month for space they don't have.

How the split works

Splitting purely by bedroom size isn't quite fair: everyone uses the kitchen, living room and hallway equally, no matter how big their bedroom is. So the rent is divided into two parts.

  • Shared space: a percentage of the rent split equally between every person. A couple counts as two people, because they both use the kitchen and the living room.
  • Bedrooms: the rest of the rent, split in proportion to each room's size. A private bathroom counts the room as a bit bigger.

Picking the shared-space percentage

There's no official number, so treat it as a dial the group agrees on. A good starting point is roughly the share of the home's floor area that's shared: if bedrooms are 450 ft² of a 900 ft² apartment, 50% is reasonable. Lower it if bedrooms are where people spend most of their time; raise it if the living room is the heart of the home.

At 0% the rent is split by bedroom size only. At 100% everyone pays the same, whatever their room.

Other things groups adjust for

  • A private bathroom or balcony: use the premium slider, which counts the room as bigger.
  • A parking space or storage unit: agree a fixed amount and take it off the rent before splitting, then add it to that person's share.
  • Utilities and internet: usually split equally per person, separately from rent.
  • Light, noise and closets: hard to measure, so most groups settle these by nudging the shared percentage or the premium.

Three common ways to split rent

  • Equal split: everyone pays the same. Simple, and fair when rooms are similar.
  • By room size: each person pays in proportion to their bedroom's square footage. Fair for bedrooms but ignores shared space.
  • Hybrid: shared space split equally, bedrooms by size, with adjustments for perks. This is what the calculator does, and what most groups settle on.
  • Some groups also split by income, so each person pays the same share of what they earn. That works for couples and close friends, but agree it in writing.

How to measure a room

Measure wall to wall at floor level and multiply length by width. A room 12 ft by 11 ft is 132 ft²; 3.5 m by 3.2 m is 11.2 m². Include built-in closets that only that room uses. For L-shaped rooms, split them into two rectangles and add them up. As long as everyone measures the same way, small errors cancel out.

Common errors

  • Measuring rooms differently

    Measure every bedroom the same way, wall to wall, and decide together whether closets count. Mixing a listing's figure with a tape measure makes the split unfair.

  • Mixing ft² and m²

    All rooms must use the same unit. The unit switch only changes the label, it doesn't convert, so a room typed in m² next to rooms in ft² looks tiny.

  • Treating a couple as one person

    Set the room to Couple. They pay for the room once but take two shares of the shared space, which is what most groups consider fair.

  • Totals off by a cent

    They won't be: amounts are rounded so they always add up to the exact rent. If your own spreadsheet disagrees by a cent, that's why.

Frequently asked questions

What's the fairest way to split rent?

Most people find a mix fairest: split the shared space equally per person and the bedrooms by size, then adjust for perks like a private bathroom. That's what this calculator does.

How should a couple split rent with a roommate?

The couple pays for their bedroom by size, like anyone else, plus two shares of the shared space. The calculator then shows what the couple pays together and each.

How much more should the room with a private bathroom pay?

There's no fixed rule. A 10–20% premium on that room's size is a common starting point. Try a few values and agree the number as a group before anyone moves in.

Should the person with the biggest room pay more?

Usually, yes, but only for the bedroom part. Everyone uses the kitchen and living room equally, so that part stays the same for everyone. That's why the split isn't purely by size.

How do you split rent by square footage?

Add up the bedroom areas, then give each person the share of rent that matches their room's share of the total. With a shared-space percentage, only the remaining rent is split by size; the calculator handles both parts.

Should utilities be split the same way as rent?

Usually not. Most groups split utilities and internet equally per person, since everyone uses them about the same, whatever the room size.

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