Retirement

Coast FIRE Calculator

Calculate your Coast FIRE number: the savings milestone where your current investments will grow to fund traditional retirement without adding another penny.

What this calculator does

The Coast FIRE Calculator estimates your result instantly from the values you enter, using standard retirement formulas. Calculate your Coast FIRE number: the savings milestone where your current investments will grow to fund traditional retirement without adding another penny. Calculations run in your browser, so nothing you type is sent to a server, and the output is an estimate for planning rather than financial advice.

About Coast FIRE Calculator

The Coast FIRE Calculator determines if your current investment balance is large enough that compound growth alone will reach your full retirement nest egg by age 65 without you ever making another contribution, allowing you to downshift careers or work part-time.

Formula & Mathematical Calculation

Coast FIRE Milestone = Full Retirement Target / ( 1 + Real Return % )^( Traditional Retirement Age - Current Age )

Calculation Example

Age 30 (Retirement Target $1.5M at Age 65, 35 Years @ 7% Real Return): Coast FIRE Number = $139,838. If you have $140k invested at age 30, you never need to save another dollar for retirement!

Key Benefits

  • Calculates exact Coast FIRE milestone for your current age
  • Identifies when you can reduce working hours or take a lower-paying dream job
  • Applies inflation-adjusted real returns (6-7%) for accurate purchasing power
  • Empowers younger professionals to design flexible lifestyles
  • 100% free financial planning tool

How to Use this Calculator

  1. Enter Current Age & Target Retirement Age
    Input your age (e.g. 28) and standard retirement age (e.g. 65).
  2. Enter Target Retirement Nest Egg ($)
    Input desired portfolio at age 65 (e.g. $1,500,000).
  3. Enter Current Invested Assets
    Input current 401(k), IRA, and brokerage balances.
  4. Calculate Coast FIRE Status
    Click Calculate to view Coast FIRE number and surplus/shortfall.

Assumptions & Limitations

What the calculation assumes

  • Every value you enter is treated as an exact, known amount.
  • Rates and contributions are assumed to stay constant for the whole period unless the form asks for them separately.
  • Results use standard financial formulas and ignore fees, penalties and promotional terms that are not entered above.
  • Inflation, tax changes and market volatility are not modelled unless a field for them is provided.
  • Amounts are unit-agnostic: results are returned in the same currency you enter.

What it does not cover

  • Coast FIRE Calculator produces estimates for education and planning, not a quote, offer or professional advice.
  • Real-world outcomes differ when fees, taxes, rounding rules or provider-specific terms apply.
  • Local regulations and tax rules vary by country and change over time; verify current rules for your jurisdiction.
  • Figures are only as accurate as the inputs you supply — check them before acting on the result.
  • For decisions with lasting financial impact, confirm the numbers with a qualified professional.

Frequently Asked Questions

Coast FIRE is the milestone where you have already saved enough in retirement accounts that compound interest will grow the balance to fully fund traditional retirement with zero future contributions.

You May Also Need

Retirement Income & Cash Flow Calculator

Calculate your total monthly retirement income by combining 401(k)/IRA withdrawa...
Traditional IRA Calculator

Calculate upfront tax deductions, tax-deferred compound growth, and future taxab...
Roth IRA Calculator

Calculate your tax-free retirement nest egg in a Roth IRA with annual contributi...

Next step: browse the full Retirement calculators or read the related guides for context before you decide.