---
title: "Coast FIRE Calculator 2026: With Social Security and Pension"
description: "Enter your age, spending and what you have invested. See your Coast FIRE number, with Social Security or a pension if you have one. No sign-up."
url: https://firenum.com/coast-fire
---

# Coast FIRE Calculator

How much do you need today to stop saving and coast to retirement?

Updated October 2026

(25x)

Monthly, at the age you claim it (your SSA statement shows it). 0 if none.

Your result

To retire at age 65:

$217,548Coast FIRE number

35 yearsTo let it grow

**You're 23% of the way to Coast FIRE.** $167,548 to go.

Left alone, your $50,000 grows to $275,801 by 65.

5.5x growth over timeat 5% annual returns after inflation

Traditional FIRE: $1,200,000

Retirement age must be greater than current age

[See when you can retire with these numbers →](/fire-planner?birth=1996&retire_age=65&expenses=4000&brokerage=50000&growth=8&currency=USD&source=calculator&calc=coast-fire)

Free. No sign-up. No ads. The Fire Planner shows how often your money lasts in 500 simulations and every start year since 1872.

## How to calculate your Coast FIRE number

Your Coast FIRE number is your FIRE number divided by one plus your real return, raised to the number of years until you retire. Your FIRE number is a year of spending divided by your [withdrawal rate](/guides/4-percent-rule). With your Coast FIRE number invested today, you can stop saving. Growth alone takes it to your FIRE number by retirement.

Formula

**Coast FIRE number = FIRE number ÷ (1 + real return) ^ years to retirement**

Spend $4,000 a month: your FIRE number is $1,200,000 ($4,000 × 12 ÷ 4%). At 30, retiring at 65, at 5% a year after inflation: $1,200,000 ÷ 1.05^35 = **$217,548**. With $2,000 a month of Social Security from 67, you need $645,266 at 65. Your Coast FIRE number drops to **$116,981**.

## What is Coast FIRE?

**Coast FIRE (also called Coast FI)** is the point where you've saved enough that compound growth alone will reach your full [FIRE number](/guides/what-is-fire) by your target retirement age, with no additional contributions needed.

Think of it as planting a tree. Once it's established and big enough, you don't need to keep watering it every day. It'll grow on its own. Your job shifts from aggressive accumulation to simply not touching what you've built.

The appeal is obvious: you can downshift to a less stressful, lower-paying job that just covers your current expenses. No more optimizing for income. No more grinding for promotions you don't want. You work to live, not to save.

The term emerged from online FIRE communities around 2018-2019 and was popularized by writers like [Jessica at The Fioneers](https://thefioneers.com/coast-fi-vs-slow-fi/), who used her own Coast FI milestone to transition to part-time work. The [r/coastFIRE subreddit](https://www.reddit.com/r/coastFIRE/) (51,000+ members) remains the largest dedicated community.

For many people, especially those who discovered FIRE later in life or who don't have high incomes, Coast FIRE is a more achievable milestone than traditional FIRE. It's proof that financial independence isn't all-or-nothing. There are meaningful waypoints along the way.

## Coast FIRE with Social Security

Before Social Security starts, your portfolio pays all of your spending. Retire at 65 with benefits from 67: the first two years come out of your savings alone.

Once the benefit starts, your portfolio only pays the gap. The calculator subtracts what the benefit is worth at your withdrawal rate. At 4%, $2,000 a month from 67 cuts the $1,200,000 target to $645,266. Enter it under “Social Security or pension”, with the age it starts (62 to 70). A pension works the same way. The numbers by age and claim age are in [Coast FIRE with Social Security](/blog/coast-fire-social-security).

## Coast FIRE Number by Age

Don't want to plug in numbers? Here's a quick reference. These assume retiring at 65 with a conservative 5% real return and a 4% withdrawal rate, the same defaults the calculator uses above.

| Current Age | Years to 65 | $3,000/mo expenses | $4,000/mo expenses | $5,000/mo expenses |
| --- | --- | --- | --- | --- |
| 25 | 40 | $127,841 | $170,455 | $213,069 |
| 30 | 35 | $163,161 | $217,548 | $271,935 |
| 35 | 30 | $208,240 | $277,653 | $347,066 |
| 40 | 25 | $265,772 | $354,363 | $442,954 |
| 45 | 20 | $339,201 | $452,267 | $565,334 |
| 50 | 15 | $432,915 | $577,221 | $721,526 |

The pattern is clear: the longer you wait, the more you need. A 25-year-old needs just $170,455 to cover $4,000/month expenses in retirement; a 50-year-old needs $577,221 (roughly 3.4× as much) for the same lifestyle. Starting early is the single biggest lever.

 ![Coast FIRE chart: saving $1,500 a month from age 25 with nothing invested, at a 5% return after inflation, the balance reaches the Coast FIRE number at age 38 with $318,000. With no more saving it grows to the $1.2 million FIRE number ($4,000 a month at 4%) by 65. A dashed line shows the Coast FIRE number at each age, from $170,000 at 25.](/assets/blog/coast-fire-chart.webp)

Coast FIRE chart for the $4,000 a month column: save until the balance crosses the dashed line at 38, then stop. Free to use under [CC BY 4.0](/terms#charts): credit firenum.com with a link.

**How sensitive are these numbers?** The table above uses a conservative 5% real return. Assume a more optimistic 7% (the long-run historical average) and the numbers drop sharply: the age 30 / $4,000\-per-month figure falls from $217,548 to $112,396 (about half). The younger you are, the more sensitive your number is to the return assumption, because small rate differences compound over more years. This is why we default to 5-6% for Coast FIRE and treat 7% as a best-case scenario.

## How Coast FIRE Works

The math behind Coast FIRE is the inverse of compound growth. Instead of asking "how much will this grow to?", you ask "how much do I need now to reach that target?" The formula and a worked example are in [How to calculate your Coast FIRE number](#how-to-calculate) above.

We use a conservative 5% real return for planning. U.S. stocks have historically returned about 7% after inflation ([Damodaran's NYU dataset](https://pages.stern.nyu.edu/~adamodar/New_Home_Page/datafile/histretSP.html) 6.9%, 1928-2024; [Shiller's Yale dataset](http://www.econ.yale.edu/~shiller/data.htm) 7.1%, 1871-2024), but planning with a lower number builds in a margin of safety. Because the return is real, every number is in today's purchasing power.

### The Variables That Matter

| Variable | Impact on Coast FI Number |
| --- | --- |
| More years to retirement | Lower Coast FI needed (more time for growth) |
| Higher expected return | Lower Coast FI needed (faster growth) |
| Higher expenses | Higher Coast FI needed (bigger target) |
| Lower withdrawal rate | Higher Coast FI needed (bigger target) |

The power of time is dramatic. At 25 with 40 years to retirement, you need $170,455 to coast. At 45 with 20 years left, you'd need $452,267 for the same retirement lifestyle (at the 5% real return used throughout this page). Starting early matters enormously.

## Coast FIRE vs Traditional FIRE

Traditional FIRE means accumulating your full retirement number as fast as possible (usually through aggressive saving of 50%+ of income), then stopping work entirely.

Coast FIRE is a waypoint, not the destination. You hit a smaller number earlier, then shift how you work rather than stopping work altogether.

|  | Traditional FIRE | Coast FIRE |
| --- | --- | --- |
| **Target** | Full FIRE number | Coast FI number (smaller) |
| **After reaching it** | Stop working (optional) | Keep working, but only for current expenses |
| **Savings rate** | High (often 50%+) | Can drop to 0% after Coast FI |
| **Timeline** | Years to full accumulation | Years to Coast FI + years of coasting |
| **Risk** | Sequence of returns in early retirement | Decades of market volatility during coasting |

Neither is inherently better. Traditional FIRE gets you to full freedom faster but requires more sacrifice. Coast FIRE lets you enjoy life sooner but means working (at least part-time) for longer. Many people end up somewhere in between. For a deeper comparison with another popular alternative, see [Coast FIRE vs Barista FIRE](/blog/coast-fire-vs-barista-fire).

## The Risks of Coast FIRE

Coast FIRE depends on a return assumption over decades. That's the fundamental bet. [Financial Samurai called it](https://www.financialsamurai.com/most-dangerous-early-retirement-strategy-coast-fire/) "the most dangerous early retirement strategy" for this reason, and while that framing is deliberately provocative, the underlying concern is legitimate.

### Return Assumptions Can Be Wrong

The 7% real return figure is a long-run average. But returns over any specific 30-40 year period have varied significantly. Someone who started investing in 1929 experienced different outcomes than someone who started in 1982. The historical range for 35-year real returns on U.S. stocks spans roughly 5% to 9% annualized, and that spread changes your Coast FI number dramatically.

### No Dollar-Cost Averaging Safety Net

When you stop contributing and coast, you lose the benefit of buying shares at lower prices during downturns. A traditional saver buying through a crash benefits from [dollar-cost averaging](https://www.investopedia.com/terms/d/dollarcostaveraging.asp). A coaster just watches their portfolio drop and hopes it recovers in time. [Research by Frank and Blanchett](https://www.financialplanningassociation.org/sites/default/files/2021-10/JUN10%20JFP%20Frank%20and%20Blanchett%20PDF.pdf) found that investors with identical average returns can see terminal values differ by 25% due to the sequence those returns arrive in.

### Expenses Change More Than You Think

The biggest critique: your expenses at 30 may bear little resemblance to your expenses at 50. Kids, healthcare costs, aging parents, housing changes. Life has a way of inflating your spending. The [Bureau of Labor Statistics](https://www.bls.gov/opub/btn/volume-9/how-have-healthcare-expenditures-changed-evidence-from-the-consumer-expenditure-surveys.htm) shows healthcare is the fastest-growing expense category for American households.

### Mitigating the Risk

None of this means Coast FIRE is a bad strategy. It means it requires honest assumptions and a buffer:

*   **Use conservative returns** (5-6% real instead of 7%) and treat any outperformance as a bonus
*   **Build a 10-20% buffer** above your Coast FI number before you stop contributing
*   **Keep some savings capacity**: even $200/month into a brokerage account keeps the muscle active
*   **Revisit yearly**: if your portfolio is tracking below the growth curve, you can adjust

How does your Coast FIRE number hold up across different market conditions? The [Fire Planner](/fire-planner) asks "Can you coast to retirement?" for your whole plan, right under the money left. It runs your plan through 500 Monte Carlo simulations by default (up to 5,000). It also replays your plan from every start year since 1872, including the years where coasting through a crash erases your margin.

For a deeper analysis of what actually happens when people start coasting (including the job, identity, and lifestyle challenges), see [The Coast FIRE Myth](/blog/coast-fire-myth).

## Who is Coast FIRE For?

Coast FIRE makes the most sense if you:

*   **Started saving young:** A 25-year-old with $50,000 invested is already close to Coast FI for many retirement targets. Time is your superpower.
*   **Want to change careers:** Hate your high-paying corporate job? Coast FI gives you permission to become a teacher, artist, or barista without sacrificing retirement security.
*   **Value present enjoyment:** Some people don't want to defer all happiness until retirement. Coast FI lets you optimize for life satisfaction now.
*   **Have variable income:** Freelancers, entrepreneurs, and gig workers can aggressively save during good years, hit Coast FI, then ride out lean years without stress.
*   **Found FIRE late:** If you're 40 with modest savings, traditional FIRE might feel impossible. Coast FI is a more realistic goal that still changes everything.
*   **Living outside the US:** The FIRE math is universal. Compound growth works the same in any currency. Use the currency selector to plan in EUR, GBP, JPY, CAD, AUD, CHF, INR, or NZD.

## After You Hit Coast FI

Reaching your Coast FI number doesn't mean you _have_ to stop saving. But it means you _can_. Based on [r/coastFIRE](https://www.reddit.com/r/coastFIRE/) discussions, the most common paths fall into two categories:

### Most People: Change the Mindset, Not the Job

The surprise finding from [our analysis of Coast FIRE discussions](/blog/coast-fire-myth): the majority of people who hit Coast FI don't quit or switch jobs. They redirect retirement contributions to travel, hobbies, and lifestyle upgrades. They set boundaries at work: "meets expectations" becomes a perfectly fine performance review. They use all their PTO, say no to extra projects, and stop optimizing for promotions. Same job, completely different relationship with it.

### Some People: Actually Change the Work

For those who do make a move, the most effective paths are consulting or contracting in their existing field (higher hourly rate, fewer hours), going part-time at their current employer, or starting a business with the safety net of Coast FI removing the pressure to be profitable immediately. The mythical "easy coast job" (low stress, decent pay, good benefits) is [much harder to find than expected](/blog/coast-fire-myth).

### The "One More Year" Trap

Warning: Coast FI can become an excuse to never make a change. "I'll just save a bit more to be safe" year after year defeats the purpose. If you've hit your number and built in a reasonable buffer, trust the math and make your move.

Coast FIRE is one of several [FIRE strategies](/fire-types). Where it fits: Lean FIRE targets minimal spending, Traditional FIRE targets full financial independence, [Barista FIRE](/barista-fire) adds part-time work, and Fat FIRE aims for a comfortable lifestyle. Coast FI sits in between. It is more accessible than Traditional and more patient than Barista.

## Further reading

*   [Helping Clients Understand When They Have Enough Retirement Savings To "Coast FIRE"](https://www.kitces.com/blog/coast-fire-career-flexibility-retirement-savings-financial-advisor-ongoing-value/) (Kitces): how financial advisors judge when a client has reached Coast FIRE, and what the bare formula leaves out.
*   [The Beauty Of Coast FIRE](https://financialpanther.com/the-beauty-of-coast-fire/) (Financial Panther): what it's like to front-load saving in your 20s, then ease off with two kids, a mortgage and daycare.
*   [What is Mini Retirement?](https://savingwithsofi.com/what-is-mini-retirement/) (Saving with Sofi): why to reach Coast FIRE before taking a long break from work.

## Frequently Asked Questions

Divide your FIRE number by one plus your real return, raised to the number of years until you retire. Your FIRE number is a year of spending divided by your withdrawal rate, which is 25 times a year of spending at 4%. Spend $4,000 a month and your FIRE number is $1,200,000. At 30, retiring at 65 at a 5% real return, that is $1,200,000 ÷ 1.05 to the 35th power = $217,548. The calculator above runs the same math for any age, return or withdrawal rate. Add Social Security or a pension and it subtracts that too.

Your Coast FIRE number is the amount you need invested today so that growth alone takes it to your FIRE number by retirement. It equals your FIRE number divided by one plus your real return, raised to the years until you retire. At 30, spending $4,000 a month and retiring at 65 at a 5% real return, it is $217,548. Reach it and you can stop saving for retirement. Anything you add after that is extra margin.

There is no universal good number. A good Coast FIRE number is the one that, left alone, grows to your own FIRE number by the age you want to retire. Your spending, your age and the return you assume set it. Spending $4,000 a month, retiring at 65, at a 5% real return with a 4% withdrawal rate, it is $170,455 at 25, $217,548 at 30, $277,653 at 35, $354,363 at 40, $452,267 at 45 and $577,221 at 50. Assume 7% instead of 5% and the age-30 number falls to $112,396. If the market then returns less, you fall short. Plan with the lower return.

At 40, spending $4,000 a month and retiring at 65, you need $354,363 invested to coast FIRE (5% real return, 4% withdrawal rate). Left alone for 25 years, it grows to a $1,200,000 FIRE number. With $2,000 a month of Social Security from 67, you need $190,549. Spend $3,000 a month and it is $265,772. At $5,000 a month it is $442,954.

It can. Before the benefit starts, your portfolio pays all of your spending. After it starts, your portfolio only pays the gap, so your Coast FIRE number drops. At 30, spending $4,000 a month and retiring at 65, $2,000 a month from 67 cuts it from $217,548 to $116,981. Enter the benefit under “Social Security or pension” in the calculator. Benefits can change over decades. The calculator also shows what you’d need without it, which is the number to plan on if you want a margin. Not sure which claim age to enter? The [Social Security break-even calculator](/social-security-break-even) compares 62, 67 and 70.

Enter what you have invested today in the calculator. The verdict under the result compares it to your Coast FIRE number: either you've reached it, and it shows what your savings grow to by retirement with no new contributions, or it shows the percentage you have and the amount still to go.

Use 5-7% for real (inflation-adjusted) returns. The U.S. stock market has historically returned about 10% nominally and 7% after inflation, based on [nearly a century of data](https://pages.stern.nyu.edu/~adamodar/New_Home_Page/datafile/histretSP.html). Using 5-6% is conservative and accounts for potential lower future returns, international diversification, or bonds in your portfolio. Avoid using nominal returns (10%+) unless you're also inflating your FIRE number target.

Yes, but differently than traditional FIRE. You're betting on decades of compound growth. A major market crash early in your coasting phase could set you back significantly. Mitigation strategies include: building a 10-20% buffer above your Coast FI number, keeping some savings capacity even while coasting, and being willing to adjust your timeline if markets underperform. The trade-off is enjoying more of your prime years in exchange for this risk.

On paper, yes: a higher expected return means a lower Coast FI number. But this is risky. If you assume 10% returns and only get 6%, your portfolio won't reach your target. It's better to use conservative assumptions (5-6%) and be pleasantly surprised than to rely on optimistic projections and fall short. You can always adjust later if returns are better than expected.

Your Coast FI number will be higher because there's less time for compound growth. For example, coasting to age 50 instead of 65 roughly doubles your Coast FI number (at a 5% real return). At some point, it makes more sense to pursue traditional FIRE with aggressive saving rather than Coast FI. Use the calculator to compare scenarios.

Coast FIRE is a milestone: the point where you have enough to stop saving. Barista FIRE is a lifestyle: working part-time (often a job with benefits, hence "barista") while your investments grow. Many people reach Coast FI and then adopt a Barista FIRE lifestyle, but they're distinct concepts. You can be Coast FI without working at all if you have other income sources, or you might work part-time before reaching Coast FI.

Yes. This calculator supports 9 currencies: USD ($), EUR (€), GBP (£), JPY (¥), CAD, AUD, CHF, INR (&rupee;), and NZD. Use the currency selector in the navigation bar to switch. All calculations work the same regardless of currency. The math behind FIRE is universal. Your preference is saved automatically.

## Coast FIRE Scenarios

### Coast FIRE at 25: The Early Saver

A 25-year-old with $3,000/month expenses needs just $127,841 to Coast FI. With 40 years of compound growth at 5% real, that becomes $900,000 by age 65. If you already have $50,000 invested at 25, you've got a meaningful head start. A few more years of saving could close the gap, then switch to whatever work you actually enjoy. [Try this scenario in the calculator](/coast-fire?currentAge=25&retirementAge=65&monthlyExpenses=3000&expectedReturn=5&withdrawalRate=4&currency=USD).

### Coast FIRE at 35: The Mid-Career Reset

At 35 with $4,000/month expenses, your Coast FI number is $277,653. You have 30 years of growth ahead. If you've saved $150,000, you're already past halfway. A couple more years of aggressive saving, and you can downshift to a lower-stress job that just covers current expenses, with no more retirement savings needed. [Try this scenario in the calculator](/coast-fire?currentAge=35&retirementAge=65&monthlyExpenses=4000&expectedReturn=5&withdrawalRate=4&currency=USD).

### Coast FIRE at 45: Is It Too Late?

At 45 with $5,000/month expenses, your Coast FI number is $565,334 with only 20 years of growth. That's a higher bar, but not impossible. And if you're flexible on timing, pushing retirement to 70 drops the number to about $442,954, a more reachable target. It's never too late to use compound growth in your favor. [Try this scenario in the calculator](/coast-fire?currentAge=45&retirementAge=65&monthlyExpenses=5000&expectedReturn=5&withdrawalRate=4&currency=USD).

Prefer a spreadsheet? The [FIRE spreadsheet](/tools/fire-spreadsheet) includes a Coast FIRE calculator tab you can customize further, or the dedicated [Coast FIRE spreadsheet](/tools/coast-fire-spreadsheet) adds a by-age coast-number matrix and a glide-path chart.

## What's Next After Your Coast FI Number?

Knowing your Coast FI number is the starting point. The [Fire Planner](/fire-planner) models your full financial picture (assets, debts, income, expenses, and life events) with month-by-month projections, Monte Carlo simulation, and stress testing. See how your Coast FI plan holds up against market crashes, inflation spikes, and career changes.

## Related Calculators

[FIRE Number Calculate your financial independence target](/fire-number) [Barista FIRE See how part-time income reduces your FIRE number](/barista-fire) [Social Security Break-Even Claim at 62, 67 or 70: the ages the choices cross](/social-security-break-even) [Compare 11 FIRE calculators How firenum stacks up against 10 other tools](/blog/fire-calculator-comparison)

About firenum.com

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