Financial Calculator
Coast FIRE Calculator
Estimate how much you need invested today to stop contributing and still reach financial independence by your target age.
Use the Coast FIRE Calculator
Your results
- FIRE number
- $0.00
- Coast FIRE number
- $0.00
- Amount above or below Coast FIRE
- $0.00
- Years until retirement
- 0 years
Year-by-Year Projection
How this calculator works
- What it does
- Estimate how much you need invested today to stop contributing and still reach financial independence by your target age.
- Inputs used
- The estimate uses current age, target retirement age, annual expenses in retirement, withdrawal rate (%), expected annual return (%), and current invested assets.
- Calculation approach
- The calculator applies the relationships defined for the coast fire calculator to those inputs and updates fire number, coast fire number, amount above or below coast fire, and years until retirement.
- How to read the result
- Treat the result as a scenario based on the values entered. Compare a few reasonable inputs and consider costs, taxes, timing, or risks that the calculator does not include.
How to Use This Calculator
- Enter Current age and Target retirement age using values that match the scenario you want to evaluate.
- Enter Annual expenses in retirement and Withdrawal rate (%) using values that match the scenario you want to evaluate.
- Enter Expected annual return (%) and Current invested assets using values that match the scenario you want to evaluate.
- Review the assumptions for the coast fire calculator, especially rates, time periods, and optional amounts.
- Select Calculate to update the results, then adjust one input at a time to compare scenarios.
Understanding the Results
- FIRE number
- The target amount calculated from the spending, rate, or goal assumptions entered above.
- Coast FIRE number
- The target amount calculated from the spending, rate, or goal assumptions entered above.
- Amount above or below Coast FIRE
- The amount above or below coast fire estimated by the Coast FIRE Calculator using current age, target retirement age, and annual expenses in retirement and the other values entered.
- Years until retirement
- The years until retirement estimated by the Coast FIRE Calculator using current age, target retirement age, and annual expenses in retirement and the other values entered.
Common Mistakes
- Treating a constant return or withdrawal rate as a guaranteed outcome.
- Leaving out inflation, taxes, fees, healthcare, or irregular retirement expenses.
- Using current spending without considering how expenses may change later.
- Relying on one scenario instead of testing more cautious assumptions.
Worked Example
Example inputs
- Current age
- 30
- Target retirement age
- 60
- Annual expenses in retirement
- $48,000
- Withdrawal rate (%)
- 4%
- Expected annual return (%)
- 7%
- Current invested assets
- $100,000
Example results
- FIRE number
- $1,200,000.00
- Coast FIRE number
- $157,640.54
- Amount above or below Coast FIRE
- -$57,640.54
- Years until retirement
- 30 years
For this illustrative scenario, the fire number is $1,200,000.00. Changing any input can materially change the result, so use the example as a walkthrough rather than a guarantee.
Frequently asked questions
What is Coast FIRE?
Coast FIRE is the point where your current investments could grow to your retirement target without additional contributions, assuming your return and timeline estimates hold.
How is my FIRE number calculated?
Your FIRE number divides estimated annual retirement expenses by your chosen withdrawal rate.
Why does compounding matter for Coast FIRE?
More years of compounding can reduce the amount needed today because investments have longer to grow before retirement.
How does the withdrawal rate affect Coast FIRE?
A lower withdrawal rate increases both your FIRE number and Coast FIRE number, while a higher rate reduces them but may increase retirement risk.
Are the investment assumptions guaranteed?
No. Actual returns vary, and inflation, taxes, fees, spending changes, and market conditions can materially affect the result.
Does Coast FIRE mean I can stop working immediately?
No. Coast FIRE means current investments may be enough to grow toward a future retirement target without new contributions. You still need income to cover current expenses until retirement.
Should I include Roth IRA and 401(k) balances in Coast FIRE?
Include invested retirement assets that are intended for long-term retirement funding, but consider account access rules, taxes, penalties, and liquidity separately.
What does the Coast FIRE Calculator calculate?
Estimate how much you need invested today to stop contributing and still reach financial independence by your target age. The result is based only on the inputs and assumptions shown on the page.