Rent Split Calculator Example: Three Methods, One Total
For the recorded test, a rent total of $2,345.67 was allocated by room, private area, and income. Each method produced a different set of shares, but each displayed set adds back to the same $2,345.67 total. This is a synthetic calculation test, not a record of a real household.
By room
Ava: $1,172.83
Ben: $586.42
Cam: $586.42
Sum: $2,345.67 · Difference: $0.00
By private area
Ava: $1,042.52
Ben: $781.89
Cam: $521.26
Sum: $2,345.67 · Difference: $0.00
By entered income
Ava: $1,108.86
Ben: $703.70
Cam: $533.11
Sum: $2,345.67 · Difference: $0.00
The test inputs
The example uses one entered rent total and three named participants. Ava is assigned to room A; Ben and Cam share room B. Each person also has an entered private-area value and income value. The calculation record does not specify the income period or whether the figures are gross or take-home pay, so those details are not inferred here.
| Person | Room ID | Entered private area | Entered income |
|---|---|---|---|
| Ava | A | 400 | 5,200 |
| Ben | B | 300 | 3,300 |
| Cam | B | 200 | 2,500 |
These are self-created test inputs. They are included to make the example reproducible; they do not describe typical rent, typical rooms, or observed renter behavior.
How the three allocations are worked out
By room. The inputs contain two distinct room IDs. Divide the rent between those rooms, then divide room B’s share between its two occupants. The recorded output is Ava $1,172.83, Ben $586.42, and Cam $586.42. The recorded amounts—not a separately reconstructed rounding rule—are used for the displayed cents.
By private area. Add the entered area values: 400 + 300 + 200 = 900. Each person’s share is the rent total multiplied by that person’s area and divided by 900. For example, Ava’s calculation is $2,345.67 × 400 ÷ 900 = $1,042.52. Applying the same ratio gives Ben $781.89 and Cam $521.26.
By entered income. Add the entered income values: 5,200 + 3,300 + 2,500 = 11,000. Each person’s share is the rent total multiplied by that person’s entered income and divided by 11,000. Ava’s calculation is $2,345.67 × 5,200 ÷ 11,000 = $1,108.86. The same calculation gives Ben $703.70 and Cam $533.11.
Check the total after each method
The room result reconciles as $1,172.83 + $586.42 + $586.42 = $2,345.67. The area result reconciles as $1,042.52 + $781.89 + $521.26 = $2,345.67. The income result reconciles as $1,108.86 + $703.70 + $533.11 = $2,345.67. In all three recorded outputs, the difference from the entered rent is $0.00.
The reconciliation is the useful comparison: the method changes who carries which share, while the recorded participant amounts still add to the same entered total. It does not show that one allocation is fairer, more common, or required by a lease.
Reproducing this example
Open the rent split calculator, enter the rent and the three rows above, and compare its room, area, and income results. The source record for this example says the deployed calculator JavaScript was executed in a Node virtual machine with a minimal DOM shim. It was not a browser-interface test, a lease interpretation, a typical-rent study, or real household data. The figures above are the saved output of that one synthetic input set.
The script used for the recorded run is the calculator’s deployed JavaScript. Its SHA-256 recorded in the source ledger is 45a10a5b41e6388847352e910e9f08174f294b5cbe7f929bb724a9f9aa154992.
The calculator’s displayed amounts are reported as recorded. The source record does not include unrounded intermediate values or a separate trace explaining how individual cents were assigned, so this page does not claim a specific cent-allocation rule for this run.