FINANCE / FINANCIAL RUNWAY
Financial Runway Calculator
How long will my savings last? Estimate your personal runway with cash, savings, investments, income, and living expenses. Adjust inflation, compare scenarios, and download a monthly CSV. Free, with no signup.
Your starting point
Start with the example, then make it yours.
Savings & investments
Optional. Enter each balance only once. Leave anything you don’t have at zero.
For regular or high-yield savings, use your account’s APY. No separate high-yield setting needed.
Include only investments you can sell to fund living costs. Total return includes reinvested dividends. Use asset income for separate net cash income, such as rental income; don’t count it again in take-home income or investment returns. Property values are not spendable balances.
Living expenses
Use a monthly total or add up your regular bills. The breakdown replaces the total; it isn’t added on top.
When switching from a changed total, it starts under Other recurring bills; split it across the categories. For annual bills, enter the yearly amount divided by 12. Count each cost in just one category.
Projection assumptions
Inflation increases your living expenses each year. For example, 3% turns $1,000 per month into about $1,030 after a year. Income stays fixed; savings APY and investment returns come from Savings & investments. These are editable estimates, not predictions.
One-time income & expenses (0)
Enter a positive amount for income or a negative amount for a cost. The event number field sets when it happens: 1 = next month, 12 = twelve months from now. Amounts are dollars in that future month.
Your numbers stay in this page’s memory. Refreshing clears your changes. No account needed.
PROJECTED DEPLETION
2 years 1 month
Your balance first reaches zero during month 25.
ADDITIONAL TAKE-HOME INCOME NEEDED TODAY
$2,000.00 / monthThis closes the gap between $3,000 in recurring monthly expenses and $1,000 in take-home and separate asset income, without drawing down savings.
This is today’s break-even amount, not a promise of unlimited runway. It excludes one-time costs and investment gains. As living costs rise, your income must rise too. The runway projection still keeps income fixed.
Advanced: fixed income for a 100-year projection
100-YEAR FIXED-INCOME ESTIMATE
$16,634 / monthAn extra $16,634 each month, starting next month, keeps the balance positive throughout the 100-year projection. That brings monthly take-home income to $17,634, plus any separate asset income.
Smallest whole-dollar increase under your current assumptions, including inflation and one-time events. The increase stays fixed. This is a 100-year estimate, not a guarantee that your balance will never reach zero.
Month-by-month breakdown (26 rows)
| Month | Cash | Savings | Investments | Total | Today’s dollars | Unfunded |
|---|---|---|---|---|---|---|
| 0 | $30,000 | $0 | $20,000 | $50,000 | $50,000 | $0 |
| 1 | $28,000 | $0 | $20,065 | $48,065 | $47,947 | $0 |
| 2 | $25,993 | $0 | $20,131 | $46,124 | $45,897 | $0 |
| 3 | $23,978 | $0 | $20,197 | $44,175 | $43,850 | $0 |
| 4 | $21,956 | $0 | $20,263 | $42,219 | $41,805 | $0 |
| 5 | $19,926 | $0 | $20,330 | $40,255 | $39,763 | $0 |
| 6 | $17,889 | $0 | $20,396 | $38,285 | $37,723 | $0 |
| 7 | $15,844 | $0 | $20,463 | $36,307 | $35,686 | $0 |
| 8 | $13,792 | $0 | $20,530 | $34,322 | $33,652 | $0 |
| 9 | $11,732 | $0 | $20,597 | $32,329 | $31,620 | $0 |
| 10 | $9,665 | $0 | $20,664 | $30,329 | $29,591 | $0 |
| 11 | $7,590 | $0 | $20,732 | $28,322 | $27,565 | $0 |
| 12 | $5,508 | $0 | $20,800 | $26,308 | $25,541 | $0 |
| 13 | $3,418 | $0 | $20,868 | $24,286 | $23,520 | $0 |
| 14 | $1,320 | $0 | $20,936 | $22,256 | $21,502 | $0 |
| 15 | $0 | $0 | $20,220 | $20,220 | $19,486 | $0 |
| 16 | $0 | $0 | $18,173 | $18,173 | $17,471 | $0 |
| 17 | $0 | $0 | $16,112 | $16,112 | $15,451 | $0 |
| 18 | $0 | $0 | $14,036 | $14,036 | $13,428 | $0 |
| 19 | $0 | $0 | $11,946 | $11,946 | $11,400 | $0 |
| 20 | $0 | $0 | $9,842 | $9,842 | $9,369 | $0 |
| 21 | $0 | $0 | $7,722 | $7,722 | $7,333 | $0 |
| 22 | $0 | $0 | $5,588 | $5,588 | $5,294 | $0 |
| 23 | $0 | $0 | $3,440 | $3,440 | $3,250 | $0 |
| 24 | $0 | $0 | $1,276 | $1,276 | $1,203 | $0 |
| 25 | $0 | $0 | $0 | $0 | $0 | $903 |
BEHIND THE NUMBERS
How the savings runway calculation works
How each month works
Savings and investments grow first, using (1 + annual rate)^(1/12) − 1. Savings use your APY; investments use an assumed total return. Income and one-time flows then enter cash, and spending leaves cash. If cash runs short, savings are withdrawn next, then investments are sold to cover the gap. Cash earns no interest; surplus income stays in cash.
Spending grows by (1 + inflation)^((month − 1)/12). Take-home income and separate asset income stay fixed. Living expenses use either your monthly total or the sum of itemized bills, never both. One-time amounts are not inflation-adjusted.
What the result means
Depletion is the first month the combined balance reaches zero (rounded to cents). The projection runs automatically until depletion, up to 100 years. Positive balances at that limit show “Beyond 100 years.” The simulation stops at depletion; unfunded spending shows any gap that month. It does not model debt or recovery from later income. No opening balance means depletion at month zero.
Totals are nominal dollars. “Today’s dollars” divides the month-end balance by accumulated inflation. The chart is a deterministic illustration, not a prediction of market performance.
What’s outside the model
Savings interest and investment returns are modeled before taxes and fees. Total return includes reinvested dividends; separate asset income must not duplicate those returns. Savings APY is held constant, although actual rates may change. Taxes on withdrawals, investment fees, withdrawal restrictions, market volatility, and changes to income are not modeled. Use take-home income and include other expected taxes in spending.
This is an educational planning tool, not financial advice. Investment returns are not guaranteed. Test lower returns and higher expenses as well as your expected case.
A simple example
With $12,000 cash, no investments, $2,000 monthly spending, and $500 monthly income, the gap is $1,500 per month. With zero inflation, the balance reaches zero at the end of month 8.
Use “Keep for comparison,” then adjust your current inputs to compare two scenarios. Downloads include the full current monthly breakdown. All amounts are USD.
Financial runway calculator: common questions
How long will my savings last?
With no inflation, interest, investment returns, or one-time events, divide available savings by your monthly shortfall: expenses minus income. For example, $12,000 divided by a $1,500 monthly shortfall lasts 8 months. This calculator uses a monthly simulation when those assumptions are more complex.
What is personal financial runway?
Personal financial runway is the time your available cash, savings, and sellable investments can cover your expenses under the income and return assumptions you enter. This tool models personal living expenses, rather than startup burn rate.
Does this savings runway calculator include inflation?
Yes. The annual inflation assumption increases recurring living expenses over time while income stays fixed. You can edit it. A small change can substantially affect a long projection because the increase compounds each year.
Can I include high-yield savings, stocks, and other income?
Yes. Enter savings with an APY, sellable investments with an assumed annual total return, and separate monthly asset income. Cash is spent first, then savings, then investments. Do not count the same balance or income twice.
What does additional take-home income needed today mean?
It is the current recurring expense shortfall after take-home and separate asset income, with a minimum of zero. For $3,000 in monthly expenses and $2,587 in income, it is $413 per month. This excludes one-time costs and does not guarantee unlimited runway.
Does Beyond 100 years mean my money will never run out?
No. The simulation stops at 1,200 months. Beyond 100 years means the balance remains positive at that limit under the selected fixed assumptions. It is not a guarantee or a retirement recommendation.
Is the calculator free, and are my numbers saved?
The calculator, scenario comparison, and CSV export are free with no signup. Financial inputs stay in page memory and are cleared on refresh. A downloaded CSV is saved to your device. Basic site analytics do not include calculator balances or results.
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