Income-Proportional Split Calculator: Fair Shares for Couples
Split rent or any shared bill by income, not 50/50. Enter the total, add each person’s monthly income, and get each person’s exact share in seconds.
People and monthly incomes
🔒 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 bill total
Type the full amount to split — rent, groceries, or any shared expense.
Add each person’s monthly income
Add a row per person and enter their monthly take-home income. Add as many people as you need.
Split proportionally
Each person’s share equals their fraction of the combined income. Earn twice as much, pay twice as much.
Worked Example
Alex and Sam split $1,500 of rent. Alex earns $4,000/month and Sam earns $2,000/month, so the combined income is $6,000. Alex’s share is 4,000 ÷ 6,000 = 66.67% and Sam’s is 33.33%:
| Person | Monthly income | Share |
|---|---|---|
| Alex | $4,000 | $1,000.00 (66.67%) |
| Sam | $2,000 | $500.00 (33.33%) |
| Total | $6,000 combined | $1,500.00 |
Frequently Asked Questions
Should I use gross or net income?
Net take-home pay is fairer, since it reflects what each person actually has available to spend.
What if someone has no income right now?
Give them an income of 0. If everyone’s income is 0, the calculator falls back to an equal split.
Is a proportional split fair for couples?
Many couples find it fairer than 50/50 when earnings differ. Agree on the approach first, then use the numbers.
Is my income 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.
- Room-Size Rent Splitter — split rent by bedroom size instead of income.
- Split by Shares Calculator — split by custom shares like 2/1/1.
- Split Bill Calculator — the classic equal split.
