Coast FIRE Calculator [Find Your Financial Freedom Number]

US retirement planning tool

Coast FIRE Calculator

Find out whether your investments could grow to your retirement target without any more contributions, and estimate when you could stop adding new retirement savings if you keep investing each month.

1. Your retirement goals

Enter annual retirement spending in today’s dollars. The calculator adjusts it for inflation by your planned retirement age.

Your current age Whole years.

Planned retirement age Must be greater than current age.

Annual spending in retirement, today’s $ Include expected housing, healthcare, taxes and everyday costs.

Other annual retirement income, today’s $ Optional. Assume it starts at retirement and increases with inflation. Leave at $0 if uncertain.

Current retirement investments ($) Invested balance available for your retirement goal; exclude your home’s value unless investable.

Monthly investment until you coast ($) Assumed invested at each month’s end until you reach Coast FIRE.

2. Investment assumptions

These are editable forecasts, not guaranteed market returns or a recommended withdrawal strategy.

Expected annual investment return (%) Nominal annual return before fees and inflation.

Annual investment fees (%) Applied as a yearly percentage reduction to gross growth.

Expected annual inflation (%) Used to convert today’s retirement costs to future dollars.

Initial retirement withdrawal rate (%) Editable retirement planning rule of thumb; not a guarantee.

Coast FIRE means the investments you already own are projected to grow to your retirement target without further contributions. It does not mean you can stop working today; you still need to cover living expenses until retirement.

Your Coast FIRE projection

Coast FIRE number today — Portfolio needed now with no more contributions

Estimated age you can coast — With planned monthly investing

Monthly savings needed to reach target — Saving every month until retirement age

Retirement portfolio goal — Inflation-adjusted to retirement-year dollars

Your Coast FIRE progress

Current invested amount —

Coast amount needed today —

Years until retirement —

Estimated after-fee annual return —

Estimated annual real return —

Projected portfolio at retirement

Future nominal dollars, before withdrawal taxes. Monthly additions use your entered contribution.

No new contributions —

Keep adding every month —

Retirement portfolio target —

The monthly-investing scenario assumes contributions continue through retirement, even if you reach Coast FIRE sooner. The coast-age estimate assumes you stop contributions at that milestone.

Retirement spending assumptions

Annual spending, today’s dollars —

Other annual income, today’s dollars —

Annual amount funded by portfolio, today’s dollars —

Inflation-adjusted portfolio spending at retirement —

Portfolio-only first-year withdrawal capacity —

Future-dollar goal shortfall without saving —

Withdrawal capacity is estimated from the projected no-contribution retirement balance multiplied by the entered withdrawal rate. It is a first-year amount, not guaranteed lifelong income.

What if investment returns change?

A two-percentage-point range around your selected gross return, with the same fees, inflation and retirement assumptions.

Investment return sensitivity
Gross annual return	Coast number today	No-contribution portfolio at retirement	Monthly contribution needed

Portfolio growth by age

All balances and Coast thresholds below are future nominal dollars for that age, rather than today’s purchasing power. The CSV includes every year.

Sample of yearly portfolio projections
Age	With no new savings	With monthly savings	Coast threshold at that age

How the Coast FIRE formula works

Retirement portfolio goal in today’s dollars = max(0, annual retirement spending − other annual retirement income) ÷ initial withdrawal rate. The future-dollar goal multiplies this amount by (1 + inflation) raised to the years until retirement.

Coast FIRE number today = future-dollar retirement portfolio goal ÷ (1 + annual after-fee return) raised to years until retirement. Equivalently, divide the goal in today’s dollars by (1 + real return) raised to the same years, where real return = (1 + after-fee nominal return) ÷ (1 + inflation) − 1.

Projected investment balance uses monthly compounding consistent with the assumed annual after-fee return. Monthly contributions are added at each month’s end. The coast-age estimate finds the first month when the current projected portfolio could meet the retirement target with no more contributions afterward.

The model uses smooth fixed annual returns and inflation. Actual investments fluctuate, and fees, taxes, market losses early in retirement, withdrawal timing and lifespan can materially change results. A 4% starting withdrawal rate is a historical rule of thumb, not a guarantee, and may be inappropriate for longer retirements.

Frequently asked questions

What is Coast FIRE?

Coast FIRE is the point when your existing retirement investments could grow to your planned retirement amount without additional contributions, assuming the modeled returns occur. You still need income to pay living expenses before retirement.

Does Coast FIRE mean I can retire immediately?

No. Coast FIRE means you may be able to stop saving for retirement while continuing to earn enough to cover current expenses. Traditional FIRE means you may already have enough invested to support present spending.

Why does the calculator ask for inflation?

$60,000 of annual expenses today will not buy the same things decades later if prices rise. This calculator inflates your retirement spending target, then uses nominal portfolio projections so the units match.

Can I count Social Security or a pension?

Only if the estimated income starts when you retire and maintains its purchasing power during retirement. Otherwise, leave other income at zero or use a separate detailed retirement cash-flow plan that models different start dates and benefit increases.

Is 4% a guaranteed safe withdrawal rate?

No. It is a common starting benchmark for a roughly 30-year retirement, but actual sustainability depends on market performance, taxes, fees, investment allocations and retirement length. The calculator lets you test a lower rate.

Does the calculator save my financial information?

Calculations take place locally in your browser; this tool does not intentionally send entered values to a separate calculator service. Other website analytics or cookie technologies may operate independently.

Educational disclaimer and sources: No return, retirement income or withdrawal rate is guaranteed. See Charles Schwab on the 4% rule and Investor.gov financial calculators. Tax treatment, account access restrictions, Social Security benefit timing and changing contributions are not modeled. Consult an appropriately qualified adviser for significant retirement decisions.