Monthly Budget Calculator
Frequency-aware cash-flow plan
Enter recurring income, spending, debt, and savings
Result
Calculation summary
Enter values to see the result
Monthly allocation preview
Where the modeled outflows go
How to use this calculator
- 1Enter primary and other income with the frequency each amount is received.
- 2Enter recurring expenses, debt payments, and planned savings with their own frequencies.
- 3Calculate to review normalized monthly cash flow, annual projection, savings rate, and spending allocation.
Formula
Monthly cash flow = normalized monthly income − normalized monthly outflows
Weekly, biweekly, semimonthly, monthly, quarterly, and annual values are annualized and divided by twelve.
Calculation steps
- Convert every recurring amount to an annual equivalent from its selected frequency.
- Divide annual equivalents by twelve to obtain comparable monthly amounts.
- Add income and outflow categories separately.
- Subtract outflows, including planned savings, from income.
- Calculate savings and debt-payment ratios against normalized monthly income.
Worked example
A 5,000 monthly income with 4,900 in monthly expenses and planned savings leaves a 100 monthly surplus and a 1,200 annual projected surplus.
Assumptions
- Each recurring amount continues for a complete representative year.
- Planned savings are treated as an outflow so the remaining amount is available after saving.
- Irregular taxes, one-time costs, account balances, and investment returns are excluded.
- No allocation rule such as 50/30/20 is treated as universally required.
Sources
Frequently asked questions
How are weekly and biweekly amounts converted?
Weekly amounts are multiplied by 52 and biweekly amounts by 26, then divided by 12 for a representative monthly average.
Why is savings counted as an expense?
It is treated as a planned cash outflow so the displayed surplus remains after the selected savings contribution.
Does the calculator enforce a 50/30/20 budget?
No. It reports the entered cash flow and ratios without presenting one allocation rule as appropriate for everyone.
Are my budget details placed in the URL?
No. Detailed income and spending amounts are kept out of share URLs by default.