Free Coast FIRE CalculatorYour Number in 30 Seconds
Get your Coast FIRE number in seconds—then see whether retirement savings can grow on their own from here.
What's Your Coast FIRE Number?
Your Coast FIRE Number
$329,443
This is the $1,250,000 retirement nest egg, discounted back to today.
You've covered 15% of the target. Gap: $279,443.
About $1,207 per month would be needed to fund the full retirement target by retirement.
Defaults: retire at 65, $0 monthly contribution, 7% nominal return, 3% inflation, 4% withdrawal
What does this number actually mean?
It's the amount you need invested today so compound growth can reach your retirement target—if you leave that money invested and earn enough from work to cover today's bills.
- •At or above the number: the estimate says you've hit Coast FIRE under these assumptions. Run a worse return and higher inflation before you cut contributions or change jobs.
- •Below it: the gap still has to be saved or grown. Raise the monthly contribution, retire later, or lower retirement spending. Those inputs are under Adjust your plan.
There isn't one good Coast FIRE number. The worked example below uses age 35, retire at 65, and $50,000 a year: about $398,578 today at 7% nominal return, 3% inflation, and a 4% withdrawal rate. Change the age or the budget and the figure moves.
Compare benchmark numbers by ageWhat does Coast FIRE actually mean?
In one sentence: You've saved enough that compound growth alone can fund retirement—even if you never invest another dollar.
Why it matters: it marks the point where retirement savings may coast, while you only need income for today's bills.
If you skip this checkpoint, it's easy to keep grinding for a full FIRE number you may not need yet—or to cut retirement contributions before the math actually works.
Doing it right helps you:
- • See a clear Coast FIRE number instead of guessing
- • Know when a lower-stress job that covers expenses becomes realistic
- • Pressure-test the answer before you change your savings plan
How does it play out?
- • Save aggressively early in your career
- • Hit your Coast FIRE number
- • Switch to a lower-stress job that just covers your expenses
- • Let your investments grow untouched until retirement
It's the halfway point to full FIRE—for people who don't want to wait until 65 to stop grinding.
Learn more about Coast FIRE →How do you use this calculator?
What's your current age?
Enter how old you are now. Younger ages need a smaller Coast number for the same retirement target, because compound growth has more years to work.
When do you want to retire, and on what budget?
Set retirement age and annual retirement spending. Earlier retirement or higher spending raises the Coast FIRE number.
What have you already invested?
Enter current invested savings you expect to leave compounding. Under Adjust your plan, you can change nominal return (default 7%), inflation (3%), and withdrawal rate.
How do you read the chart?
Orange is projected investments. Blue is the Coast target at each age. A crossing is the first age the projection says you've hit Coast FIRE. No crossing before retirement means this monthly contribution is not enough under the assumptions you entered.
How is the Coast FIRE number calculated?
Three linked amounts: growth after inflation, the full nest egg at retirement, and the smaller amount today that could grow into that nest egg.
What's the real return?
Nominal return is growth before inflation. Real return is what's left after inflation eats into it.
With a 7% nominal return and 3% inflation, the real return is about 3.88%.
The calculator does not treat 7% as a real return—that 7% is the editable nominal default.
How big is the retirement nest egg?
This is the full amount you want invested by the retirement date—not today's Coast number.
Example: $50,000/year ÷ 4% = $1,250,000 needed at retirement
The nest egg is the retirement-date target. Today's Coast FIRE number is smaller.
How do you get today's Coast number?
Discount the nest egg back to today using real return and years left until retirement.
Where:
- Real Return = (1 + Return Rate) ÷ (1 + Inflation) - 1
- Years = Retirement Age - Current Age
Example: Age 35, retire at 65, 7% return, 3% inflation
Real Return = (1.07 ÷ 1.03) - 1 = 3.88%
Coast Number = $1,250,000 ÷ (1.0388)^30 = $398,578
At age 35, $398,578 is the amount that would grow to the $1,250,000 retirement target if the selected assumptions hold and the money remains invested.
Sources and research basis
AAII hosts the Cooley, Hubbard and Walz research. Historical withdrawal results do not guarantee a future outcome.
The SEC states that past performance does not necessarily predict future results. The 7% nominal return is an editable assumption.
BLS publishes the Consumer Price Index. The calculator uses your inflation input rather than predicting future inflation.
Sources last reviewed: July 25, 2026
What counts as current savings?
Count money already invested that you expect to leave compounding for retirement.
Usually include
- Retirement accounts such as a 401(k), 403(b), traditional IRA or Roth IRA
- Taxable brokerage investments set aside for retirement
Usually keep separate
- Emergency cash and money reserved for near-term spending
- Your primary home unless your plan converts home equity into retirement assets
- Future income, employer matches not yet received, pensions and Social Security
This calculator does not adjust for taxes by account type. Use the amount available to your plan, and get tax advice when account treatment could change the decision.
How do you stress-test the result?
One estimate cannot show how sensitive the answer is. Run it again with:
- A lower nominal return
- Higher inflation
- A lower withdrawal rate
- Then compare the Coast number, required monthly contribution and retirement shortfall with your first run
This is a sensitivity check—not a forecast or a best/worst-case range.
What does this calculator leave out?
This is an educational estimate, not financial, tax or investment advice. It uses the return, inflation, withdrawal and contribution assumptions you enter. It does not model:
- Taxes on contributions, growth or withdrawals
- Investment fees or changes in asset allocation
- Sequence-of-returns risk from uneven annual market results
- Withdrawal rules, penalties or required distributions for specific accounts
- Life expectancy, healthcare shocks or changes in retirement spending
- Market guarantees or the probability that a plan succeeds
Talk with a qualified financial professional before reducing retirement contributions or changing your work plan.
Planning in Canada, the UK, or India?
This page is a USD estimate without CPP, State Pension, or similar benefits. Use the country calculator so currency and local retirement income are in the inputs.
Sources last reviewed: July 25, 2026
Common Coast FIRE questions
The calculator starts with a 7% nominal return and 3% inflation—about a 3.88% real return: (1.07 ÷ 1.03) - 1.
Past returns do not predict future results. Review the inputs, then stress-test a less favorable set.
Yes. Coast FI is a shorter way to say Coast FIRE (FI = financial independence).
This tool calculates the same number: how much you need invested today so compound growth can carry you to retirement.
Recheck the inputs and the risks the model leaves out before changing your plan.
Coast FIRE still assumes you cover current expenses and leave retirement investments untouched. Taxes, fees and future returns can move the outcome—get professional advice before cutting contributions or changing work.
Traditional FIRE: Save until you can quit work forever. Usually requires 25x annual expenses.
Coast FIRE: Save until compound growth handles retirement. Then work for living expenses only.
Coast FIRE is the halfway point to full FIRE.
Markets rarely return the smooth annual rate used here—order of returns can matter.
Healthcare is a concrete one: US coverage before Medicare (65) is expensive, so budget $500–1,000/month per person if you're not employer-covered. Taxes, fees, withdrawal rules and spending changes can also move the result. This calculator does not model those items or estimate a success probability.
Higher inflation lowers real return when nominal return stays fixed, so today's Coast number rises.
Example at age 35, retire at 65, $50,000 annual expenses, 7% nominal return: about $398,578 at 3% inflation vs $532,595 at 4%. Change the inflation input to check your own result.
Yes. Use the dedicated For Couples calculator.
The homepage stays intentionally simple. For household planning, open Couples to enter both partners' ages, savings, monthly contributions and retirement dates.
You can compare combined and separate paths there without changing the homepage estimate.
Have more questions? Drop us a line.
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"It's not that I don't want to work hard—I just want to work hard for myself."
May you reach the shore soon 🌅