Purchase Impact on FIRE Timeline
See how a one-time purchase affects the time it takes to reach financial independence.
Earnings & Spending
Your annual after-tax income. Used to estimate how much you can save each year.
How much you spend per year while working.
How much you expect to spend per year in retirement. Used to calculate your FIRE number.
Current Portfolio
Total value of your current invested portfolio. Includes retirement and taxable investment accounts.
The upfront cost of the purchase you’re considering. Assumed to be paid immediately and reduces your invested assets.
Investment Parameters
Expected average annual investment return before inflation.
Expected long-term annual inflation rate.
Percentage of your portfolio you plan to withdraw annually in retirement. Commonly 3–4%, based on historical data (not guaranteed).
FIRE Number
The estimated portfolio value needed to fund your retirement spending indefinitely. Typically calculated as annual retirement spending divided by your withdrawal rate.
Amount you save and invest each year. Calculated as take-home pay minus current spending.
Time to FIRE Comparison
Without Purchase
Without this purchase, you are 11 years, 7 months, 20 days away from FIRE.
With Purchase
With this purchase, you are 11 years, 9 months, 10 days away from FIRE.
Purchase Impact
This purchase extends your estimated time to FIRE by 1 month, 20 days.
Every dollar you spend today is a dollar that won’t compound for your future.
About this calculator
This calculator shows how a one-time purchase affects your timeline to Financial Independence (FIRE) by comparing your projected FIRE date with and without the purchase.
Instead of focusing on whether a purchase is “good” or “bad,” the calculator helps quantify the opportunity cost — how spending money today may delay future financial independence.
Use this tool to make informed trade-offs between present enjoyment and long-term goals.
What each input means
- Annual take-home pay is your annual after-tax income. Used to estimate how much you can save each year.
- Current annual spending is how much you spend per year while working.
- Retirement annual spending is how much you expect to spend per year in retirement. Used to calculate your FIRE number.
- Current investments is the total value of your current invested portfolio. Includes retirement and taxable investment accounts.
- One-time purchase price is the upfront cost of the purchase you’re considering. It’s assumed to be paid immediately and reduces your invested assets.
- Investment growth rate is your expected average annual investment return before inflation.
- Inflation rate is the expected long-term annual inflation rate.
- Safe withdrawal rate is the percentage of your portfolio you plan to withdraw annually in retirement. Commonly 3–4%, based on historical data (not guaranteed).
How does spending impact your FIRE timeline?
Every dollar you invest has the potential to grow through compounding. When you make a one-time purchase, you’re not just spending the purchase price — you’re also giving up the future growth that money could have generated.
This calculator models two scenarios: investing the money instead of making the purchase, and making the purchase while investing a smaller portfolio. The difference between these two paths shows up as a change in your FIRE date.
The impact depends on how large the purchase is relative to your portfolio, how long the money would have had to compound, and your savings rate and investment returns.
Smaller purchases may have little impact, while larger purchases made earlier can meaningfully extend the time to financial independence.
Key levers that influence purchase impact
- Size of the purchase – Larger purchases remove more capital from compounding.
- Time horizon – Purchases made earlier have a larger long-term impact.
- Savings rate – Higher ongoing savings can offset the impact of one-time spending.
- Investment returns – Higher returns increase the opportunity cost of spending.
- Withdrawal rate – More conservative withdrawal rates require larger portfolios, magnifying delays.
Key assumptions & limitations
- Constant returns – Investment returns are assumed to be constant.
- No market volatility modeled – Market volatility and sequence-of-returns risk are not modeled.
- Steady inflation – Inflation is applied at a steady rate.
- Simplified taxes – Taxes are simplified and not dynamically calculated.
- Estimates only – Results are estimates, not financial advice.
This calculator is designed for high-level planning and behavioral insight, not precise forecasting.