Coast FIRE Calculator

The Point Where You Can Stop Contributing and Still Get There

Coast FIRE marks the moment your existing savings, left alone with no further contributions, will grow through compounding alone into a full FIRE number by your target retirement age. Reach that point and you're free to cover only current living expenses — through a lower-stress job, part-time work, or a career break — without derailing eventual financial independence. This calculator works out how much that "coast point" balance actually is at your current age.

The Formula

FIRE Number = Annual Expenses at Retirement ÷ Withdrawal Rate
Coast FIRE Number = FIRE Number ÷ (1 + r)^years

The Coast FIRE number is simply the FIRE number discounted backward from retirement age to today at your expected annual return — the present value needed for compounding alone to finish the job.

Where This Calculation Matters

Deciding to downshift careers — once you've coasted, additional income only needs to cover today's expenses, not retirement savings too.
Evaluating a sabbatical or lower-paying passion job — knowing your coast number tells you whether pausing contributions now still leaves retirement on track.
Early aggressive saving strategies — because the coast number shrinks the more time compounding has to work, reaching it early (in your 20s or 30s) requires a much smaller balance than reaching it in your 40s or 50s.
Milestone-based motivation — coast FIRE gives a concrete, earlier target than full FIRE, which can be motivating for long-horizon savers.

Coast FIRE Number by Current Age

Amount needed today to coast to a $1,500,000 FIRE number by age 65 ($60,000 annual expenses, 4% withdrawal rate, 7% annual return), by current age
Current age	Years to grow	Coast FIRE number needed today
25	40	$100,170.57
30	35	$140,494.41
35	30	$197,050.68
40	25	$276,373.77
45	20	$387,628.50
50	15	$543,669.03
55	10	$762,523.94

The required balance roughly doubles for every 10-11 years less time compounding has to work at a 7% return.

How to Use This Calculator

Enter your current age and planned retirement age.
Enter your current investable savings.
Enter your expected annual expenses in retirement.
Enter your expected annual return rate.
Enter your target withdrawal rate, or leave the 4% default.
Select Calculate to see your Coast FIRE number and whether your current savings have already reached it.

Related Calculations

See the full contribution-driven path with the FIRE Calculator, or model continued part-time income after coasting with the Barista FIRE Calculator.