Find your Coast FIRE number instantly. See if you can already stop saving for retirement, how long until you can coast, and compare Coast FIRE vs Barista FIRE vs Traditional FIRE side by side. Inflation-adjusted with 3 calculation modes.
✓Verified: Trinity Study, Bengen 4% Rule, Bureau of Labor Statistics CPI Data — 2026
Enter your current situation. The calculator tells you your Coast FIRE number and whether you have already reached it.
Your age today
Enter your current age (18–70).
When you want to retire
Enter retirement age (must be after current age).
$
Today’s dollars — inflation is built in
Enter expected annual spending.
$
401k + IRA + brokerage (not cash/home)
Enter current investments (0 or more).
$
Annual income — reduces portfolio needed
How much you withdraw per year from portfolio
Inflation-adjusted — already accounts for 2–3% inflation
Not at Coast FIRE yet? Enter your details to see how long until you reach it and how much you need to save each month.
Your age today
Enter your current age.
When you want to stop working
Enter retirement age.
$
Expected yearly expenses in retirement
Enter annual spending.
$
What you have invested today
Enter current investments.
$
How much you invest each month
Enter monthly contribution.
Inflation-adjusted annual return
Compare Coast FIRE, Barista FIRE, and Traditional FIRE side by side for your specific situation.
Enter current age.
Enter retirement age.
$
Enter annual spending.
$
For Barista FIRE: annual part-time earnings
$
Current portfolio value
Enter current investments.
Coast FIRE Number
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⚠️ Disclaimer: This calculator is for educational purposes only. Results are estimates based on your inputs and historical averages. Actual returns, inflation, and Social Security payments will differ. Consult a licensed financial advisor before making retirement decisions. Past market performance does not guarantee future results.
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Sources & Methodology
✓All formulas verified against peer-reviewed financial research. Coast FIRE calculations use the present value formula derived from standard compound interest mathematics.
The foundational research establishing the 4% safe withdrawal rate. Published in the Journal of Financial Planning. Source for the 4% rule used in all FI Number calculations on this page.
The Trinity Study (1998, updated 2011) confirmed the 4% withdrawal rate across 30-year retirement periods. Used as the basis for FI Number calculations. Source of the safe withdrawal rate framework used in all three calculator modes.
Source for historical US stock market returns. The 7% real return default in this calculator is based on the historical inflation-adjusted S&P 500 average return since 1928. Updated annually.
Historical inflation data used to validate the real return rate assumption. The 7% real return incorporates approximately 3% long-term historical inflation as measured by BLS CPI.
Coast FIRE Formula:
Coast FIRE Number = FI Number ÷ (1 + real return rate)years to retirement
FI Number = (Annual Spending − Annual SS/Pension) ÷ Safe Withdrawal Rate
Real Return = Nominal Return − Inflation (historically ~7% for US equities)
Last reviewed: April 2026
The Complete Guide to Coast FIRE — Formula, Numbers by Age, and Strategy
Coast FIRE is one of the most powerful concepts in personal finance: reach a specific investment milestone early in life, then let compound interest carry your portfolio to full retirement without another dollar of saving. This guide covers the Coast FIRE formula, Coast FIRE numbers by age, and how it compares to every other type of FIRE.
Coast FIRE Number = FI Number ÷ (1 + Real Return)Years to RetirementFI Number = Annual Retirement Spending ÷ Safe Withdrawal Rate
Example — Age 35, retiring at 65, spending $60,000/year:
FI Number = $60,000 ÷ 0.04 = $1,500,000
Years to retirement = 65 − 35 = 30 years
Coast FIRE Number = $1,500,000 ÷ (1.07)30 = $1,500,000 ÷ 7.61 = $197,100 Meaning: If you have $197,100 invested today at age 35, you never need to contribute another dollar to retirement.
Coast FIRE Number by Age (Reference Table)
The following table shows your Coast FIRE number at each age, assuming $60,000 annual retirement spending, 4% safe withdrawal rate, 7% real return, and retirement at age 65. Your number scales linearly with spending — for $50,000/year spending, multiply by 0.833.
Age
Years to Retire (65)
FI Number ($60K spend)
Coast FIRE Number
Growth Multiple
25
40 years
$1,500,000
$99,700
15.0×
28
37 years
$1,500,000
$121,700
12.3×
30
35 years
$1,500,000
$140,500
10.7×
32
33 years
$1,500,000
$162,100
9.3×
35
30 years
$1,500,000
$197,100
7.6×
38
27 years
$1,500,000
$240,000
6.3×
40
25 years
$1,500,000
$277,100
5.4×
45
20 years
$1,500,000
$387,600
3.9×
50
15 years
$1,500,000
$542,800
2.8×
55
10 years
$1,500,000
$762,300
2.0×
💡 The earlier you hit Coast FIRE, the smaller your number. A 25-year-old needs only $99,700 while a 45-year-old needs $387,600 for the same retirement lifestyle. Every year you delay costs you compound growth. The difference between starting at 25 vs 35 is $97,400 — but the 25-year-old gets 10 extra years of not worrying about retirement savings.
Coast FIRE vs Barista FIRE vs Traditional FIRE vs Lean FIRE
The FIRE movement has multiple variants. Understanding how they differ helps you choose the right target for your situation. All examples assume $60,000 annual expenses, 4% SWR, 7% real return, current age 35, retirement at 65.
FIRE Type
What It Means
Amount Needed (Example)
Still Work?
Best For
Coast FIRE
Stop saving; let investments compound to retirement
~$197,000
Yes, full-time (for expenses only)
Career flexibility, golden handcuff escape
Barista FIRE
Semi-retire now; part-time work covers the gap
~$875,000
Yes, part-time
Those who want partial freedom now
Traditional FIRE
Full financial independence; stop working entirely
$1,500,000
No (optional)
Complete freedom
Lean FIRE
Full FIRE on minimal spending (<$40K/year)
<$1,000,000
No (optional)
Minimalists, low cost-of-living areas
Fat FIRE
Full FIRE with high spending ($100K+/year)
$2,500,000+
No
High earners, luxury lifestyle
Flamingo FIRE
Halfway to traditional FIRE; half-time work
~$750,000
Yes, half-time
Gradual transition to full FIRE
The Real Return Rate — What 7% Actually Means
The 7% real return is not an arbitrary number. It is derived from the historical annualized inflation-adjusted return of the US stock market (S&P 500) since 1926, calculated by multiple financial researchers including Damodaran at NYU Stern. In nominal terms, the S&P 500 has averaged approximately 10% per year. Subtracting approximately 3% for long-term average inflation gives the 7% real return. This means your purchasing power grows at 7% annually in a diversified stock index fund.
⚠️ The 7% real return is a historical average, not a guarantee. Individual years range from −50% to +50%. Sequence of returns risk — getting bad returns early in your coast period — is the primary risk in Coast FIRE planning. A buffer of 15-20% above your Coast FIRE number significantly improves resilience.
How Social Security Affects Your Coast FIRE Number
Social Security and pension income dramatically reduce your Coast FIRE number because they reduce how much your portfolio needs to generate. If you expect $24,000 per year from Social Security and need $60,000 per year total, only $36,000 per year needs to come from your portfolio. This reduces your FI Number from $1,500,000 to $900,000 — and your Coast FIRE number at 35 from $197,100 to $118,200. Always include expected Social Security or pension income in Mode 1 above for an accurate number.
What to Do After You Reach Coast FIRE
Reaching Coast FIRE unlocks career and lifestyle flexibility that most people do not realize they have. You can switch to a lower-stress job that covers your living expenses without building retirement savings. You can work part-time, move to a lower cost-of-living area, start a business, or take time off between jobs. The psychological shift from "I must maximize income" to "I only need to cover expenses" is transformative. Many Coast FIRE practitioners report significantly higher job satisfaction after reaching the milestone because they choose work they enjoy rather than work that maximizes savings rate.
Reduce working hours: Switch to 4-day weeks or part-time if your expenses allow
Change careers: Move to lower-income work you find meaningful — teaching, nonprofits, creative work
Escape golden handcuffs: Leave high-stress, high-income jobs that felt mandatory before Coast FIRE
Geographic arbitrage: Move to lower cost-of-living area — reduces expenses and may let you coast sooner
Reassess periodically: Recalculate every 2–3 years for market performance and life changes
Keep a buffer: Aim for 10–20% above your Coast FIRE number before stopping contributions
Coast FIRE Risks and How to Mitigate Them
Coast FIRE carries real risks that must be managed. The three primary risks are sequence of returns risk (bad markets early in your coast period), longevity risk (living longer than your portfolio can sustain), and lifestyle inflation (spending more in retirement than planned). Mitigation strategies include maintaining a 15-20% buffer above the calculated Coast FIRE number, reassessing every two to three years, and using conservative return assumptions (5-6% real return rather than 7%) for greater safety margin.
Coast FIRE for Couples
Couples calculate Coast FIRE on combined invested assets against combined retirement spending. If you and your partner both expect Social Security, both amounts reduce your FI Number. Calculate your combined FI Number (combined annual spending minus combined SS/pension income, divided by SWR), then calculate your combined Coast FIRE Number. Note that couples generally have lower per-person expenses in retirement due to shared housing and fixed costs — many couples use $80,000-$100,000 as their combined retirement spending estimate.
Frequently Asked Questions
Coast FIRE is the point where your invested portfolio is large enough that compound growth alone will carry it to your full retirement target by your retirement age, without any additional contributions. You still work to cover current living expenses, but you never need to save for retirement again. The name comes from coasting on a bicycle — once you have enough momentum, you stop pedaling and coast to the finish line.
Coast FIRE Number = FI Number ÷ (1 + real return rate)years until retirement. Your FI Number = annual retirement spending ÷ safe withdrawal rate (typically 4%). The real return rate (typically 7%) is already inflation-adjusted. Example: $60,000 spending, 4% SWR, 7% return, 30 years: FI Number = $1,500,000. Coast FIRE Number = $1,500,000 ÷ (1.07)30 = $197,100.
Coast FIRE: Stop saving for retirement, continue working full-time to cover current expenses, investments compound untouched until traditional retirement. You need less saved now (~$197K at 35) but work longer. Barista FIRE: Semi-retire now, work part-time to cover the gap between expenses and portfolio withdrawals (~$875K needed). You need more saved but get partial freedom immediately. Many people achieve Coast FIRE first, then keep saving toward Barista or traditional FIRE.
This calculator uses the real return rate, which already subtracts inflation. When you use 7%, you are using the inflation-adjusted historical average — meaning all values are in today's purchasing power. You enter your current spending in today's dollars, and the calculator automatically handles the inflation component by using real (inflation-adjusted) returns throughout. You do not need to enter a separate inflation rate.
Count only invested assets you will not touch until retirement: traditional 401(k), Roth 401(k), traditional IRA, Roth IRA (full balance if near retirement, or contributions-only basis if young), taxable brokerage accounts, pension cash value, and similar long-term accounts. Do NOT include: emergency fund, high-yield savings account, home equity, cash, or cryptocurrency you plan to spend soon. The calculation assumes these assets compound untouched.
Yes — and it is one of the most powerful wealth strategies. At 30 with a 65-year retirement target, you have 35 years for compound interest to work. For $60,000 annual spending, you need approximately $140,500 invested at 30. Many high-income earners achieve this by saving aggressively from age 22 to 30 in a low-cost-of-living situation, then switching to more enjoyable but lower-income careers. Saving $20,000 per year from 22 to 30 with 7% returns produces approximately $235,000 — well past Coast FIRE.
4% is the standard (Trinity Study, Bengen research) and works for 30-year retirement periods. Use 3.5% if you will retire before 55 and face a 40+ year withdrawal period. Use 4.5% if you have significant Social Security or pension income covering part of your expenses, or if you have other income sources (rental income, part-time work) in retirement. The default of 4% is appropriate for most people retiring at 60-65.
It depends on your age and spending. $500,000 at 7% real return grows to $3.8M over 30 years. If you need $150,000/year in retirement (4% of $3.75M), $500,000 is exactly enough to coast at age 35. If you need $60,000/year (4% of $1.5M), you needed only $197,000 at 35 — so $500,000 puts you significantly past Coast FIRE. Use Mode 1 above with your specific inputs for your exact answer.
A crash right after reaching Coast FIRE is the primary risk. If your portfolio drops 40%, you may fall below your Coast FIRE number and need to resume contributions. Best practices: (1) Build a 15-20% buffer above your Coast FIRE number before stopping contributions. (2) Reassess every 2-3 years. (3) Coast FIRE reached at a younger age is more resilient — you have decades to recover from crashes. (4) Use 6% real return assumption instead of 7% for a more conservative Coast FIRE number.
Yes, for the most accurate number. Social Security income directly reduces how much your portfolio needs to generate. If you need $60,000/year and expect $20,000/year from Social Security, your portfolio only needs to cover $40,000/year. This reduces your FI Number from $1,500,000 to $1,000,000 and your Coast FIRE Number at 35 from $197,100 to $131,400. Enter your expected SS income in Mode 1 for an accurate, personalized number.
Maintain a growth-oriented portfolio during your coasting years. Coast FIRE typically spans 20-35 years before traditional retirement — you need growth to hit your FI Number. Most Coast FIRE practitioners recommend: 80-90% equities (low-cost index funds: S&P 500, total market, or international funds), 10-20% bonds or other assets as you approach retirement age. Do not shift to a conservative portfolio prematurely — you need the 7% real return assumption to hold over the full coasting period.
Research shows the 4% rule has a very high historical success rate even for 40-year periods. However, some researchers recommend 3.5% for retirements longer than 35 years to improve safety margin. If you plan to stop working entirely at 50 and live to 90, use 3.5% in the calculator. If you will have part-time income or Social Security supplementing withdrawals during a long retirement, 4% remains appropriate.
Anyone with retirement savings has some investments, but Coast FIRE is a specific mathematical threshold. You have reached Coast FIRE only when your current portfolio, growing at a reasonable real return rate, will reach your full retirement target by your target retirement date without any additional contributions. Below that threshold, you still need to keep contributing. Above it, contributions are optional. This calculator tells you exactly whether you have crossed that threshold.