1
Enter Your Ages
Add your current age and the age when you expect to begin retirement withdrawals.
Financial Independence Planning Tool
Coast FIRE Calculator
Calculate how much you need invested today so compound growth can carry your portfolio toward financial independence by retirement.
Enter Your Financial Details
Adjust the assumptions to match your retirement plan.
Simple Process
How to Use the Coast FIRE Calculator
Follow these four steps to estimate whether your current investments can grow into your retirement target.
2
Add Your Investments
Enter the amount currently invested for long-term growth in retirement and brokerage accounts.
3
Set Your Assumptions
Provide your retirement spending, expected investment return, inflation and withdrawal rate.
4
Review Your Results
Compare your invested savings with your Coast FIRE number and review any remaining contribution gap.
What Is Coast FIRE?
Coast FIRE is a financial independence milestone. You reach it when your current retirement investments are large enough to grow into your required retirement portfolio without any additional contributions.
After reaching this point, you still need enough employment or business income to cover your current living expenses. However, you may no longer need to save aggressively for retirement because compound growth is expected to do the remaining work.
This approach can give people more flexibility to change careers, work fewer hours, start a business or choose work based on personal satisfaction rather than maximum income.
What Is a Coast FIRE Number?
Your Coast FIRE number is the amount that needs to be invested today so it can potentially grow into your financial independence target by your planned retirement age.
Coast FIRE formula
Coast FIRE Number = Retirement Portfolio Target ÷
(1 + Real Return Rate)Years Until Retirement
The calculator first estimates your retirement portfolio target using your desired annual retirement spending and safe withdrawal rate.
Retirement portfolio formula
Retirement Portfolio Target = Annual Retirement Spending
÷ Withdrawal Rate
Why Inflation Matters
A 7% investment return does not necessarily mean your purchasing power grows by 7%. Inflation reduces the real value of future money. This calculator therefore estimates a real return using both your expected investment return and expected inflation rate.
Real return formula
Real Return = ((1 + Nominal Return) ÷ (1 + Inflation)) - 1
Example Coast FIRE Calculation
Suppose a 30-year-old wants to retire at age 60 and spend $50,000 per year in retirement. Using a 4% withdrawal rate, the required retirement portfolio would be approximately $1,250,000 in today's purchasing power.
If the estimated real return is about 4.39% per year, the person would need roughly $344,000 invested at age 30 for that amount to grow to approximately $1.25 million by age 60, assuming the investment assumptions are achieved.
What the Results Mean
- Coast FIRE number: The estimated amount required in your investment portfolio today.
- Retirement portfolio target: The portfolio value needed at retirement based on your desired spending and withdrawal rate.
- Projected current investments: The estimated future value of your existing investments if you make no additional contributions.
- Coast FIRE gap: The difference between your current investments and your calculated Coast FIRE number.
- Monthly contribution needed: The estimated monthly investment required to reach the target by retirement under the selected assumptions.
Planning Benefits
Why Use Our Coast FIRE Calculator?
Get more than a single number with a detailed view of your financial independence progress.
Compound Growth Estimate
See how your existing investments may grow over the years without adding future retirement contributions.
Inflation-Adjusted Return
The calculation uses an estimated real return to present values in today's purchasing power.
Progress Measurement
Compare your current investments with your Coast FIRE target through a clear progress indicator.
Savings Gap Analysis
Find out how much additional money you may need before reaching your Coast FIRE milestone.
Custom Assumptions
Adjust retirement age, spending, investment returns, inflation and withdrawal rate.
Responsive Design
Use the calculator comfortably on desktop computers, tablets and mobile devices.
Coast FIRE vs Traditional FIRE
Traditional FIRE usually means accumulating enough money to stop relying on employment income completely. Coast FIRE is different because you continue working to pay current living expenses while allowing your existing investments to grow toward retirement.
Coast FIRE
- You continue earning enough to cover current expenses.
- You may reduce or stop retirement contributions.
- Your existing investments continue compounding.
- You generally retire at a traditional or selected age.
Traditional FIRE
- Your investment portfolio covers both current and future living expenses.
- You may leave full-time employment before traditional retirement age.
- You begin portfolio withdrawals earlier.
- You usually need a significantly larger portfolio today.
Important Factors to Consider
Coast FIRE calculations depend heavily on assumptions. Investment returns are not guaranteed, and actual inflation may differ from your estimate. Your retirement spending may also change because of healthcare, housing, taxes, family responsibilities or lifestyle choices.
Review your calculation regularly and consider using conservative assumptions. A financial professional can help you evaluate taxes, account types, investment risk, pension income, Social Security and other personal factors.
Common Questions
Coast FIRE Calculator FAQs
Learn more about Coast FIRE, investment growth and retirement planning assumptions.
Coast FIRE means you have invested enough money that, with sufficient time and investment growth, your portfolio may reach your retirement target without additional retirement contributions.
The calculator estimates your retirement portfolio target and discounts that amount back to its required value today using your real investment return and the number of years until retirement.
Not necessarily. Coast FIRE normally assumes you continue earning enough to pay your present living expenses. Your investments remain untouched so they can potentially grow until retirement.
Use a reasonable long-term return estimate based on your investment mix. A conservative assumption can reduce the risk of overstating future portfolio growth. Remember that returns are never guaranteed.
Inflation reduces future purchasing power. Including inflation helps the calculator express your retirement target and Coast FIRE number in today's money.
A safe withdrawal rate is the percentage of your retirement portfolio you expect to withdraw during the first retirement year. The appropriate rate depends on retirement length, investments, fees, taxes and market conditions.
If your current investments equal or exceed your Coast FIRE number, the calculator will show that you are on track under the selected assumptions. You may still choose to keep investing to build a larger safety margin.
No. This tool provides an educational estimate only. It cannot account for every tax, investment, healthcare or personal financial factor.