Net Income Calculator Formula
Understand the math behind the net income calculator. Each variable explained with a worked example.
Formulas Used
Net Income (Surplus)
net_income = monthly_income - total_expensesTotal Expenses
expense_total = total_expensesExpense-to-Income Ratio
expense_ratio = total_expenses / monthly_income * 100Variables
| Variable | Description | Default |
|---|---|---|
monthly_income | Monthly Income(USD) | 5000 |
housing | Housing (Rent/Mortgage)(USD) | 1500 |
utilities | Utilities & Bills(USD) | 300 |
food | Food & Groceries(USD) | 500 |
transport | Transportation(USD) | 400 |
other_expenses | Other Expenses(USD) | 600 |
total_expenses | Derived value= housing + utilities + food + transport + other_expenses | calculated |
How It Works
How to Calculate Net Income
Subtract all monthly expenses from your monthly income to find your surplus (or deficit).
Formula
Net Income = Monthly Income - Total Expenses
A positive number means you have money left for savings or discretionary spending. A negative number means you are spending more than you earn.
Worked Example
$5,000 monthly income with $3,300 in total expenses.
- 01Total expenses = $1,500 + $300 + $500 + $400 + $600 = $3,300
- 02Net income = $5,000 - $3,300 = $1,700
- 03Expense-to-income ratio = $3,300 / $5,000 = 66.0%
Frequently Asked Questions
What is a healthy expense-to-income ratio?
Keeping total expenses below 80% of income is a good target, leaving at least 20% for savings. Below 70% is excellent.
What should I do with surplus income?
Prioritize: 1) Build an emergency fund (3-6 months expenses), 2) Pay off high-interest debt, 3) Contribute to retirement, 4) Save for other goals.
What if my expenses exceed my income?
Review each expense category for cuts. Reduce discretionary spending first, negotiate bills, consider additional income sources, and avoid new debt.
Ready to run the numbers?
Open Net Income Calculator