Coast FIRE Calculator (Free, 2026)
Calculate when you can stop saving for retirement and let compound interest do the work. Your Coast FIRE number depends on your target retirement nest egg, which is shaped by your chosen safe withdrawal rate.
Example: A 30-year-old with $272k today coasts to $1.5M by 65 (5% real return assumption)
How Coast FIRE Works
Compound Interest
See how long-term compounding can grow your current balance without further contributions.
The Coast Strategy
Once you hit your Coast number, you never 'need' to save for retirement again. Work for passion, not survival.
Your Freedom Date
Estimate the age your inputs reach the Coast FIRE threshold and compare alternative assumptions.
Coast FIRE Numbers by Age (2026)
How much you need today to coast to $1.5M by age 65 (assuming 5% real returns)
| Your Age | Years to 65 | Coast FIRE Number | Growth Multiple |
|---|---|---|---|
| Age 25 | 40 years | $213,069 | 7.0× |
| Age 30 | 35 years | $271,935 | 5.5× |
| Age 35 | 30 years | $347,066 | 4.3× |
| Age 40 | 25 years | $442,954 | 3.4× |
| Age 45 | 20 years | $565,334 | 2.7× |
| Age 50 | 15 years | $721,526 | 2.1× |
| Age 55 | 10 years | $920,870 | 1.6× |
How to read this: Each row shows how much you would need invested today to reach $1.5M by 65 at the 5% real (inflation-adjusted) planning assumption. An age-25 balance has 40 years to grow by about 7.0×; each five-year delay raises the required starting balance by about 28%. See the formula for the equation and worked examples.
What is Coast FIRE?
Coast FIRE (also called Coast FI) is the point where you have saved enough in retirement accounts that compound interest alone will grow your portfolio to your full retirement number by age 65 — without any additional contributions. Once you reach Coast FIRE, you only need to earn enough to cover your current living expenses. You no longer need to save for retirement.
The math is straightforward present-value compounding. For the equation, step-by-step worked examples, and a lookup table by age, see our Coast FIRE formula breakdown.
Coast FIRE differs from traditional FIRE in one key way: you continue working, but you choose jobs based on fulfillment rather than salary. A software engineer earning $150,000 might switch to teaching yoga or working at a national park — any job that covers rent, food, and health insurance. The psychological shift is significant: work becomes optional rather than obligatory.
The biggest risk in Coast FIRE is sequence of returns. If the market drops 40% early in your coast period, your timeline extends significantly. Most Coast FIRE practitioners build a 10-20% buffer above their calculated number to absorb volatility. Learn more about managing this risk in our safe withdrawal rate guide.
Frequently Asked Questions
What is Coast FIRE?
Coast FIRE is when you have saved enough that compound interest will grow your investments to your retirement goal without additional contributions. You can "coast" - work a lower-paying job or part-time - since you no longer need to save. It's the point where time becomes your investment partner.
How do I calculate my Coast FIRE number?
Use the calculator above. Enter your current age, target retirement age, expected return rate, and your FI Number — it computes your Coast FIRE number instantly and shows year-by-year growth projections. Want to see the math by hand? Read our Coast FIRE formula breakdown for the equation, step-by-step worked examples, and a reference table.
Is a Coast FI number the same as a Coast FIRE number?
Yes. Coast FI and Coast FIRE are the same concept — the savings balance that grows to your full FI number by retirement age with no further contributions. Some communities drop the "RE" (retire early) because coasting usually means downshifting work rather than retiring. This calculator computes your Coast FI number either way.
What is a good Coast FIRE number by age?
Assuming $60k/year retirement spending ($1.5M FI number), the site's 5% real return default, and retirement at 65: Age 25 = $213k, Age 30 = $272k, Age 35 = $347k, Age 40 = $443k, Age 45 = $565k, Age 50 = $722k. Each five-year delay raises the required balance by about 28%.
What return should I use for Coast FIRE?
This calculator defaults to 5% real (after-inflation) returns so the result stays in today's dollars. It is a planning assumption, not a forecast. Test lower and higher scenarios, keep real and nominal figures consistent, and avoid using a nominal return against a today's-dollar retirement target.
How does a pension affect my Coast FIRE number?
A pension DRAMATICALLY reduces your Coast FIRE number. If you need $60k/year but have a $30k pension starting at 65, you only need your portfolio to generate $30k—cutting your FI number in half. Teachers, military, and government employees often reach Coast FIRE much sooner than they realize. Our calculator accounts for future income sources.
How is Coast FIRE different from a traditional 401(k) plan?
Coast FIRE isn't an alternative to a 401(k) — it's a strategy that can use one. The difference is when you stop contributing. With Coast FIRE, you front-load contributions, then stop once growth alone is projected to reach your retirement target. For example, about $347k at age 35 grows to $1.5M at 65 under the 5% real assumption, with no further contributions.
How is Coast FIRE different from Barista FIRE?
Key difference: With Coast FIRE, you DON'T touch your investments—you let them grow untouched until traditional retirement (65). You work to cover current expenses only. With Barista FIRE, you WITHDRAW from investments now while working part-time. Coast FIRE needs less upfront ($200-400k) but you work longer. Barista FIRE needs more ($500k-$1M) but you semi-retire sooner.
What happens after I reach Coast FIRE?
You can downshift: take a lower-paying job you enjoy, go part-time, change careers, or start a passion project. You only need to earn enough to cover current living expenses—not save for retirement. Many people find this removes the "golden handcuffs" and lets them escape toxic workplaces.
Can I reach Coast FIRE in my 20s or 30s?
It may be possible with a high early savings rate. Investing $20k at the end of each year from 22 through 29 grows to about $191k by age 30 at 5% real returns; left untouched, that becomes about $1053k at 65. Every $1 invested at 25 becomes about $7.04 at 65 under the same assumption.
What is Coast FIRE for teachers?
Teachers often have defined benefit pensions that change the math dramatically. A teacher with a $35k/year pension at 62 needs their 401(k)/403(b) to cover far less. Plus, many teachers qualify for PSLF (student loan forgiveness). We have a dedicated Coast FIRE for Teachers calculator that factors in pension income.
Coast FIRE by Income
See how your salary affects your path to Coast FIRE.
Coast FIRE by Life Situation
Explore educational scenarios for common household situations.
Coast FIRE by Career
Career-specific guidance for your profession.
Explore Other FIRE Strategies
Withdrawal & Retirement Planning
Once you reach Coast FIRE, your next step is planning how to withdraw from your portfolio. Your Coast FIRE number depends on your safe withdrawal rate assumption — most calculations use the 4% rule, but newer research suggests dynamic strategies may work better.
4% Rule Calculator
Test if your retirement portfolio can sustain your lifestyle using the 4% rule.
Withdrawal Strategy Comparison
Compare retirement withdrawal strategies: 4% Rule vs Guyton-Klinger vs VPW.
Safe Withdrawal Rate Guide
Deep dive into safe withdrawal rates for early retirees, with 2026 research.
Monte Carlo Simulator
Run 1,000 simulations to see the odds your portfolio survives a full retirement.
Not financial advice. This calculator is for educational purposes only and does not constitute financial, tax, or investment advice. Results are estimates based on the inputs you provide and historical data. Consult a qualified financial advisor for personalized guidance. Read our editorial guidelines.