— Budgeting
Cash Flow Calculator
See where your money goes each month and what is left. Enter income and expenses by category to build a personal cash-flow statement with net cash flow, savings rate, ratios, and a Sankey view of every dollar.
Monthly surplus
$1,400
- Total income
- $6,500
- Total expenses
- $4,300
- Moved to savings
- $800
- Savings rate
- 33.85%
- Housing ratio
- 27.69%
- Debt-service ratio
- 7.69%
- Needs vs 50%
- 56.92%
- Wants vs 30%
- 9.23%
- Committed (fixed) spend
- 60.47%
- Annualized surplus
- $16,800
Try: $6.5k in, healthy surplus, Living paycheck to paycheck, Running a deficit, With a bonus & rental
— Your monthly cash-flow statement
| Item | Amount | % of income |
|---|---|---|
| Primary income | $6,000 | 92.31% |
| Other income | $500 | 7.69% |
| Total income | $6,500 | 100% |
| Housing | $-1,800 | 27.69% |
| Utilities & bills | $-300 | 4.62% |
| Food & groceries | $-700 | 10.77% |
| Transport | $-400 | 6.15% |
| Debt payments | $-500 | 7.69% |
| Everything else | $-600 | 9.23% |
| Total expenses | $-4,300 | 66.15% |
| Savings & investments | $-800 | 12.31% |
| Net cash flow | $1,400 | 21.54% |
— Where the money flows
Download— How it works
Net cash flow = total income − total expenses − money moved to savings. Savings rate = (net flow + explicit savings) ÷ income. Each category is shown as a share of income; needs/wants/savings are mapped against the 50/30/20 reference.
Your personal profit & loss
Businesses live by their income statement; your household deserves the same clarity. This lays your month out as a proper financial statement: income at the top, expenses itemised by category below with each shown as a percentage of income, the money you move to savings on its own line, and the net cash flow ruled off at the bottom. A surplus in green means you’re living within your means and building wealth; a deficit in red means the opposite, and the statement shows exactly which categories to look at. Crucially, savings is kept separate from expenses — money you save isn’t money you’ve spent, and treating it as an outflow rather than a cost keeps the picture honest.
Worked example — $6,500 in, $4,300 of expenses, $800 to savings: Net cash flow = $6,500 − $4,300 − $800 = $1,400 surplus. That’s a 34% savings rate, and $16,800 a year flowing into your future.
The ratios that matter
Totals tell you whether you’re in the black; ratios tell you whether you’re healthy. Housing is the big one — above 35–40% of income and you’re house-poor, with little room for anything else. Debt servicing above 40% is a recognised red flag, the point at which repayments crowd out living. The calculator also maps your spending against the familiar 50/30/20 guide — needs, wants, savings — as a comparison, not a commandment: it shows where you sit versus the reference so you can judge for yourself. And the fixed-versus-variable split is a quiet measure of resilience: the more of your spending that’s committed, the less you can flex if income falls.
Following the flow
The Sankey diagram is the centrepiece — every stream of income flowing left to right and fanning out into the categories that consume it, with the surplus flowing through to savings. Nothing makes the shape of your finances clearer: you see at a glance what dominates, what’s trivial, and how thin or fat the surplus really is. Switch to the bar view for a ranked list, or read the statement itself, which is built to print like a broadsheet financial page. Use net, take-home income and don’t forget irregular costs — enter a twelfth of annual bills. This is a planning tool, not financial advice, but few exercises are as clarifying as watching your own money flow.
— Reader questions
What is a personal cash flow statement?
A monthly summary of money in versus money out — your personal profit-and-loss. Income at the top, expenses by category, savings separately, and the net cash flow at the bottom. It shows where your money goes and whether you’re running a surplus or a deficit.
Is money I save an expense?
No — money moved to savings or investments is still yours; it’s just in a different pot. The calculator shows it as an outflow on its own line, separate from true expenses, so your statement reconciles and your savings rate is measured correctly.
How much of my income should go to housing?
A common guideline is no more than 30–35% of gross, or up to about 40% of net, on housing. Above that and you’re “house-poor” — too much of your income is committed to rent or mortgage, leaving little for everything else.
What is a healthy debt-to-income ratio?
Total debt payments above 40% of income is widely treated as a red flag, the level at which repayments start to crowd out essentials and saving. Below 20% is comfortable. The calculator flags your debt-service ratio against these thresholds.
What does the fixed vs variable split tell me?
It measures resilience. Fixed costs — rent, loan EMIs, insurance — are hard to cut quickly; variable ones flex. The higher your committed (fixed) percentage, the less room you have to adapt if your income drops, which matters in an emergency.