Loading the page...
Preparing tools and content for you. This usually takes a second.
Preparing tools and content for you. This usually takes a second.
Fetching calculator categories and tools for this section.
Learn how to calculate Coast FIRE number with our free calculator and formula guide. Calculate your Coast FIRE number using the formula: Annual Expenses × 25. Use our coastfire calculator, coast fire calculator, and coast fire number calculator to determine how much you need to save to reach financial independence. Example: $40,000 annual expenses × 25 = $1,000,000 Coast FIRE number. Our calculator uses compound interest principles to determine how much you need to save to reach financial independence by retirement age.
Last updated: February 2, 2026
Need a custom financial calculator for your platform? Get a Quote
| Year | Age | Contributions | Growth | Total |
|---|---|---|---|---|
| 0 | 30 | $0 | $3,500 | $53,500 |
| 1 | 31 | $3,106 | $3,745 | $60,351 |
| 2 | 32 | $3,106 | $4,225 | $67,682 |
| 3 | 33 | $3,106 | $4,738 | $75,525 |
| 4 | 34 | $3,106 | $5,287 | $83,918 |
| 5 | 35 | $3,106 | $5,874 | $92,898 |
| 6 | 36 | $3,106 | $6,503 | $102,507 |
| 7 | 37 | $3,106 | $7,175 | $112,789 |
| 8 | 38 | $3,106 | $7,895 | $123,790 |
| 9 | 39 | $3,106 | $8,665 | $135,561 |
| ... and 26 more years | ||||
You need $259/month to reach Coast FIRE in 35 years. After that, you can stop contributing and let compound interest work.
Your Coast FIRE number of $1,000,000 is based on the 4% rule:$40,000 × 25 = $1,000,000.
With 7.0% annual returns, your money will grow from $50,000 to $1,000,000 by retirement.
You'll contribute $108,710 total over 35 years to reach Coast FIRE status.
Coast FIRE Number = Annual Expenses × 25
Determine your annual expenses in retirement:
Example: $40,000/year in retirement expenses
Apply the Coast FIRE formula:
Coast FIRE Number = Annual Expenses × 25
Example: $40,000 × 25 = $1,000,000 Coast FIRE number
Determine how much your current savings will grow:
Future Value = Current Savings × (1 + Return Rate)^Years
Example: $50,000 × (1.07)^35 = $533,829
Calculate the gap you need to fill:
Required Savings = Coast FIRE Number - Future Value
Example: $1,000,000 - $533,829 = $466,171 needed
Determine how much to save monthly:
Use annuity formula or our calculator to find monthly contribution needed to reach Coast FIRE number by retirement age.
Example: $1,200/month for 35 years
Note: These examples assume 7% annual return and retiring at 65. The younger you are, the less you need saved because compound interest has more time to work.
FIRE strategy
Coast FIRE Planning
Comprehensive financial independence planning and analysis
4% rule calculation
Annual Expenses × 25
Uses the 4% rule to determine your Coast FIRE target
FIRE strategies
Lean, Regular, Fat FIRE
Compare different FIRE strategies and approaches
Retirement planning
Age-based Strategy
Age-specific retirement planning and savings strategies
Strategy planning
Personalized Approach
Customized Coast FIRE strategies based on your situation
Savings calculation
Monthly Contributions
Determines required monthly savings for Coast FIRE
Same as Coast FIRE
Coastfire = Coast FIRE
Coastfire is the same as Coast FIRE (just written as one word)
For a 30-year-old with $50,000 savings, $40,000 annual expenses, 7% returns, retiring at 65:
Coast FIRE Number
$1,000,000
Monthly Contribution
$1,200
Our Coast FIRE calculator uses the 4% rule and compound interest calculations to determine your financial independence number. The calculation applies financial planning principles to determine how much you need to save to reach Coast FIRE status by your target retirement age.
Coast FIRE Number = Annual Expenses × 25Based on the 4% rule: you can withdraw 4% annually from your portfolio in retirement
The 4% rule states you can safely withdraw 4% of your portfolio annually:
Once you reach your Coast FIRE number, you can stop aggressive saving and let compound interest grow your investments to your full FIRE number by retirement age.
Shows the path from current savings to Coast FIRE number
Coast FIRE is a financial independence strategy where you save enough money early in life so that, without additional contributions, your investments will grow to your full FIRE number by traditional retirement age. This allows you to "coast" to financial independence.
Need help with other retirement planning? Check out our retirement ROI calculator and investment growth simulator.
Get Custom Calculator for Your PlatformResult: Coast FIRE Number = $1,000,000, Monthly Contribution = $1,200
Save $1,200/month for 35 years to reach Coast FIRE, then let compound interest work.
25-year-old, $20,000 savings, $30,000 expenses, 8% returns
Coast FIRE: $750,000, Monthly: $800
40-year-old, $100,000 savings, $50,000 expenses, 6% returns
Coast FIRE: $1,250,000, Monthly: $2,500
Share it with others who need help with Coast FIRE planning
Suggested hashtags: #CoastFIRE #FinancialIndependence #FIRE #Retirement #Calculator