Slow FIRE Calculator
The year and age work becomes optional at your current savings pace. Live Slow FIRE calculator with worked steps, charts and a year-by-year projection table.
Calculator
What you have invested today, excluding home equity and emergency cash.
How much you invest each month toward independence.
Nominal yearly investment return before inflation. 7% is the long-run US stock average.
What you expect to spend per year once work is optional, in today's dollars.
The share of the portfolio you draw each year. 4% is the classic Trinity-study starting point.
This fire planning calculator runs on the standard FIRE model: yearly spending divided by a safe withdrawal rate sets the target, and savings compound monthly at the return you enter.
Year-by-year projection
Starting balance, yearly contributions, investment growth and end balance — nominal dollars at the return entered above.
| Year | Start balance | Contributions | Growth | End balance |
|---|---|---|---|---|
| 2026 · Yr 1 | $40,000 | $9,600 | +$2,736 | $52,336 |
| 2027 · Yr 2 | $52,336 | $9,600 | +$3,496 | $65,432 |
| 2028 · Yr 3 | $65,432 | $9,600 | +$4,304 | $79,336 |
| 2029 · Yr 4 | $79,336 | $9,600 | +$5,162 | $94,098 |
| 2030 · Yr 5 | $94,098 | $9,600 | +$6,072 | $109,770 |
| 2031 · Yr 6 | $109,770 | $9,600 | +$7,039 | $126,409 |
| 2032 · Yr 7 | $126,409 | $9,600 | +$8,065 | $144,074 |
| 2033 · Yr 8 | $144,074 | $9,600 | +$9,155 | $162,829 |
| 2034 · Yr 9 | $162,829 | $9,600 | +$10,311 | $182,740 |
| 2035 · Yr 10 | $182,740 | $9,600 | +$11,539 | $203,879 |
| 2036 · Yr 11 | $203,879 | $9,600 | +$12,843 | $226,323 |
| 2037 · Yr 12 | $226,323 | $9,600 | +$14,228 | $250,150 |
| 2038 · Yr 13 | $250,150 | $9,600 | +$15,697 | $275,447 |
| 2039 · Yr 14 | $275,447 | $9,600 | +$17,257 | $302,305 |
| 2040 · Yr 15 | $302,305 | $9,600 | +$18,914 | $330,819 |
| 2041 · Yr 16 | $330,819 | $9,600 | +$20,673 | $361,091 |
| 2042 · Yr 17 | $361,091 | $9,600 | +$22,540 | $393,231 |
| 2043 · Yr 18 | $393,231 | $9,600 | +$24,522 | $427,353 |
| 2044 · Yr 19 | $427,353 | $9,600 | +$26,627 | $463,580 |
| 2045 · Yr 20 | $463,580 | $9,600 | +$28,861 | $502,041 |
| 2046 · Yr 21 | $502,041 | $9,600 | +$31,233 | $542,874 |
| 2047 · Yr 22 | $542,874 | $9,600 | +$33,752 | $586,226 |
| 2048 · Yr 23 | $586,226 | $9,600 | +$36,426 | $632,251 |
| 2049 · Yr 24 | $632,251 | $9,600 | +$39,264 | $681,116 |
| 2050 · Yr 25 | $681,116 | $9,600 | +$42,278 | $732,994 |
| 2051 · Yr 26 | $732,994 | $9,600 | +$45,478 | $788,072 |
| 2052 · Yr 27 | $788,072 | $9,600 | +$48,875 | $846,547 |
| 2053 · Yr 28 | $846,547 | $9,600 | +$52,482 | $908,628 |
| 2054 · Yr 29 | $908,628 | $9,600 | +$56,311 | $974,539 |
| 2055 · Yr 30 | $974,539 | $9,600 | +$60,376 | $1,044,515 |
| 2056 · Yr 31 | $1,044,515 | $9,600 | +$64,692 | $1,118,807 |
| 2057 · Yr 32 | $1,118,807 | $9,600 | +$69,274 | $1,197,681 |
| 2058 · Yr 33 | $1,197,681 | $9,600 | +$74,139 | $1,281,420 |
| 2059 · Yr 34 | $1,281,420 | $9,600 | +$79,304 | $1,370,323 |
| 2060 · Yr 35 | $1,370,323 | $9,600 | +$84,787 | $1,464,710 |
Results
Time to Financial Independence
32 years 8 months
$1,250,000 needed at 4.00% withdrawals.
2059
67 years old
$1,250,000
$40,000
$800
6.00%
Live results update as you type — currently showing time to financial independence of 32 years 8 months. Replace the defaults with your own spending, savings and return for an exact plan.
Visualizations
Investment Growth Each Year
Contributions vs Growth
Projected Portfolio Growth to FI
Formula
Projects current savings plus monthly contributions forward with compound growth until the trajectory crosses the FIRE number, then converts the months remaining into a calendar year and an age.
Alternative Form
Variables
| Symbol | Name | Unit | Description |
|---|---|---|---|
| S | Annual spending | currency | What the portfolio must cover each year |
| w | Withdrawal rate | decimal | Yearly draw as a decimal (4% → 0.04) |
| F | FIRE number | currency | S ÷ w — the portfolio that sustains the spending |
| P | Starting principal | currency | Amount invested today |
| PMT | Monthly contribution | currency | Deposited at each month-end |
| r | Monthly return | decimal | Annual return ÷ 12 ÷ 100 |
| n | Months | count | Years × 12 |
Explanation
Keep saving exactly as entered and the portfolio crosses the independence target in the time shown.
Step-by-Step Calculation
Follow each step to understand how the result is calculated from your inputs.
Turn yearly spending and the withdrawal rate into the target portfolio.
Project the current savings plus monthly contributions forward with compound growth.
Convert the months remaining into a calendar year and an age.
Worked Examples
See how the calculator works with different scenarios.
Scenario
The slow fire calculator run on the values above, showing the full calculation path rather than only the answer.
Inputs
Calculation
1. Turn yearly spending and the withdrawal rate into the target portfolio. → $1,250,000 target 2. Project the current savings plus monthly contributions forward with compound growth. → Target reached in 32 years 8 months 3. Convert the months remaining into a calendar year and an age. → 2059 at age 67
Result
Time to Financial Independence: 32 years 8 months
Interpretation
Keep saving exactly as entered and the portfolio crosses the independence target in the time shown.
Understanding Your Result
Your Result: Time to Financial Independence: 32 years 8 months
Typical range: With $800/month invested at 6.00%, each extra $500/month typically pulls the date forward by 1–3 years.
What This Means
Keep saving exactly as entered and the portfolio crosses the independence target in the time shown.
Why It Matters
32 years 8 months to $1,250,000 (2059, age 67); contributions $353,600 vs growth $899,348.
Professional Interpretation
32 years 8 months to $1,250,000 (2059, age 67); contributions $353,600 vs growth $899,348.
How this is calculated
Projects current savings plus monthly contributions forward with compound growth until the trajectory crosses the FIRE number, then converts the months remaining into a calendar year and an age.
What drives the result
Money you do not spend buys freedom twice: once by adding to the portfolio, and again by lowering the target the portfolio must hit. That double effect is why the savings rate predicts the timeline far better than income does. Compounding then does the heavy lifting — the last half of the journey is usually faster than the first because growth overtakes contributions.
Recommendations
- •Automate the monthly contribution the day income arrives — consistency beats timing.
- •Re-run the date yearly; raises should flow to contributions before lifestyle.
Educational Content
Introduction
Financial independence means a portfolio large enough that work becomes optional. The whole FIRE framework rests on one relationship: yearly spending divided by a safe withdrawal rate equals the portfolio you need. Every figure on this page — the number, the date, the gap, the progress — is derived from that single relationship, which is why changing spending moves everything at once.
Concept Explanation
Money you do not spend buys freedom twice: once by adding to the portfolio, and again by lowering the target the portfolio must hit. That double effect is why the savings rate predicts the timeline far better than income does. Compounding then does the heavy lifting — the last half of the journey is usually faster than the first because growth overtakes contributions.
Applications
Benefits
- •Replaces a vague retirement dream with a number and a date
- •Shows exactly which lever — spending, saving, return — moves the date most
- •Makes partial freedom (Coast, Barista) visible long before full independence
- •Produces charts and steps you can revisit every year with fresh figures
Limitations
- •Uses nominal dollars and a fixed return — real markets are lumpy and inflation bites
- •Ignores taxes, fees and health-cover costs unless you include them in spending
- •The 4% rule was tested on 30-year retirements; 50-year retirements need extra margin
- •Sequence-of-returns risk means two identical averages can produce different outcomes
Best Practices
- •Track real spending for 3–6 months before locking in any target
- •Price plans at 4% but sanity-check them at 3.5% before acting
- •Automate contributions the day income arrives
- •Re-run the numbers yearly — raises should flow to savings before lifestyle
Common Misconceptions
Practical Tips
- •Automate contributions the day income arrives
- •Funnel raises to savings before lifestyle absorbs them
- •Re-run the date yearly with fresh balances
- •Model a 1–2 point lower return as a stress test
Common Mistakes
Assumptions
This calculator makes the following assumptions to provide estimates:
Limitations
Be aware of these limitations when using this calculator:
Frequently Asked Questions
Answers to common questions about this calculator.
Why does an extra $500 a month move the date so much?
What if the date says "out of reach"?
Should I count home equity?
Who uses the slow fire calculator?
How accurate is the slow fire calculator?
How accurate is this Slow FIRE calculation?
Should I use nominal or inflation-adjusted returns?
Does this account for taxes and fees?
How often should I revisit my Slow FIRE plan?
Related Calculators
Explore more calculators related to this topic.
Related Guides
Deepen your understanding with these educational resources.
How the FIRE number, Coast and Barista variants fit together in one plan.
Why the savings rate predicts the FI date better than income does.
The 4% rule, flexible strategies and sequencing risk in early retirement.
Glossary
Technical terms used in mortgage calculations explained in plain language.
- FIRE number
- Annual spending divided by the safe withdrawal rate — the portfolio that makes work optional.
- Compounding
- Growth earning its own growth — the curve that makes late-journey progress faster than early progress.
- Runway
- How long savings alone fund current spending with no new income.
Authoritative References
Trusted sources and standards referenced by this calculator.
Applicable Standards
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Page Information
2026-09-22
2.0.0
- Federal Reserve — Survey of Consumer Finances (household wealth data)
- Bureau of Labor Statistics — Consumer expenditures and inflation (CPI)
- Social Security Administration — Retirement benefits planner
- IRS — Retirement plan contribution limits and withdrawal rules
- Trinity study update — Bengen on safe withdrawal rates
- Consumer Financial Protection Bureau — Planning for retirement
Free to use for educational and professional purposes.