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FinCalculate

Retirement Calculator

This retirement calculator projects what your balance reaches by the age you pick, then converts it into the after-tax monthly income it actually supports. Two figures matter more than the balance itself: what it pays you, and how much of it you never had to save.

Example numbers

35 years old

65 years old

Across all retirement accounts.

Yours and any employer contribution together, before tax.

Before inflation. A diversified portfolio has historically returned around 7% before inflation.

Assumptionscontribution rises each year by, tax rate in retirement, annual withdrawal rate

A step-up on each anniversary, in line with pay rises.

Applied to the whole balance, since a traditional 401(k) or IRA is taxed on withdrawal.

The share of the balance drawn each year. 4% is the common rule of thumb.

Result

The answerfrom an example

Saving this way you reach $1,601,263 by 65, about $4,163 a month after tax.

Worked on 35 now, retiring at 65, $50,000 saved, $800 a month at 7%. Change anything below to use yours.

Balance at 65
$1,601,263
After tax on withdrawal
$1,248,985
Income it supports
$4,163 a month

The figures behind it

Balance at 65
$1,601,263
After 30 years of saving.
After tax on withdrawal
$1,248,985
A traditional account is taxed in full at withdrawal, here at 22%.
Income it supports
$4,163 a month
$49,959 a year, drawing 4.0% of the after-tax balance.
You will contribute
$389,454
Between now and retirement, with the annual increase applied.
Growth does the rest
$1,161,809
72.6% of the final balance is money you never contributed.
Every extra $100 a month
$149,430
Added to the balance at retirement, before tax.
Balance at retirement, before tax$1,601,263
  • Saved already$50,000
  • Future contributions$389,454
  • Investment growthThe part you do not have to save.$1,161,809

The balance against what you put in

Net worth over time under both scenariosBalance ends at $1.6M. What you put in ends at $439K. The same figures appear in the payment schedule below.$0$500K$1M$1.5M$2M161116212630

Years from today

BalanceWhat you put in
Payment scheduleShow

The table scrolls sideways

YearMonthly inPaid in to dateGrowth to dateBalance
1$800$59,600$3,929$63,529
2$816$69,392$8,841$78,233
3$832$79,380$14,824$94,203
4$849$89,567$21,967$111,534
5$866$99,959$30,370$130,329
6$883$110,558$40,138$150,696
7$901$121,369$51,385$172,755
8$919$132,397$64,235$196,631
9$937$143,645$78,817$222,462
10$956$155,117$95,274$250,392
11$975$166,820$113,758$280,578
12$995$178,756$134,431$313,188
13$1,015$190,931$157,470$348,401
14$1,035$203,350$183,062$386,412
15$1,056$216,017$211,410$427,427
16$1,077$228,937$242,732$471,669
17$1,098$242,116$277,260$519,376
18$1,120$255,558$315,246$570,804
19$1,143$269,269$356,958$626,227
20$1,165$283,255$402,685$685,940
21$1,189$297,520$452,738$750,258
22$1,213$312,070$507,451$819,521
23$1,237$326,912$567,179$894,091
24$1,262$342,050$632,309$974,358
25$1,287$357,491$703,250$1,060,741
26$1,312$373,241$780,447$1,153,687
27$1,339$389,305$864,372$1,253,678
28$1,366$405,692$955,537$1,361,228
29$1,393$422,405$1,054,487$1,476,892
30$1,421$439,454$1,161,809$1,601,263

What this result assumes

  • Every figure is nominal, in future dollars, not today’s. At 3% inflation, money loses roughly half its purchasing power over 24 years, so a balance that looks large will not buy what the same number buys now.
  • The return is held constant. A real portfolio does not deliver 7% every year, and the order in which good and bad years arrive matters enormously near retirement, which a smooth curve cannot show.
  • The whole balance is treated as traditional pre-tax money and taxed in full on withdrawal. Roth balances are not taxed, so if some of yours is Roth this understates the after-tax figure.
  • The withdrawal rate is applied to the balance at retirement and is not projected forward. It is a rule of thumb for sizing an income, not a spending plan, and the well-known 4% figure came from a US historical study with assumptions of its own.
  • Social Security, pensions, contribution limits, fees and required minimum distributions are all excluded.

Methodology

Reviewed

The projection

The balance is run month by month from today to your retirement age. Each month it grows at one twelfth of the annual return, then the contribution is added at the end of the month — the conservative convention, since a contribution earns nothing in the month it is made. Contributions step up on each anniversary by the annual increase you set, which is how a percentage-of-salary contribution behaves when your salary rises.

Money is held in whole cents and growth is rounded to the cent each month, so a forty-year projection cannot accumulate floating-point drift. The lump-sum case is checked in the test suite against the closed form A = P(1 + r)ᵗ.

The whole balance is treated as traditional pre-tax money and taxed in full at the rate you enter when it comes out. If part of yours is Roth, the after-tax figure shown here is too low by that share.

The two figures that matter more than the balance

The first is how much of the final balance you never contributed. On a thirty-year horizon that share is usually well over half, and it is the entire argument for starting early: the growth is compounding on contributions you made decades ago, not on the ones you are making now.

The second is what the balance actually pays you. A large number is not an income. Applying a withdrawal rate to the after-tax balance turns it into a monthly figure you can compare against what you spend today, which is the only comparison that answers the question you came with.

The 4% default is a rule of thumb, not a law. It comes from a study of historical US market returns over thirty-year retirements and carries all the assumptions of that study — a particular asset mix, a particular country, a particular century. Treat it as a way to size a number, not as a spending plan.

What a smooth curve cannot tell you

Every figure here is nominal — in the dollars of the year you retire, not today’s. At 3% inflation, purchasing power roughly halves over 24 years. A projection showing a million dollars in 2056 is not describing a million dollars as you understand the amount now, and no adjustment for that is applied.

The return is also constant, which no market is. The order in which good and bad years arrive barely matters early on and matters enormously in the decade before and after you stop working, because a bad sequence hits a large balance you have started drawing from. This model has nothing to say about that risk, and the single line it draws should not be read as a forecast.

Contribution limits, employer matches, plan fees, Social Security, pensions and required minimum distributions are all outside the model. Fees in particular compound against you exactly the way returns compound for you: a 1% annual fee over thirty years is not 1%, it is roughly a quarter of the final balance.

Assumptions

  • The return is constant every year, with no volatility and no sequence-of-returns risk.
  • Contributions are made at the end of each month and never missed.
  • The annual increase applies on each anniversary rather than gradually.
  • The entire balance is traditional pre-tax money, taxed in full at withdrawal.
  • The tax rate in retirement is the single rate you enter, applied to the whole balance.
  • The withdrawal rate is applied once to the balance at retirement and not projected forward.
  • Every figure is nominal. Inflation is not applied to the balance or to the income it supports.
  • Contribution limits, catch-up contributions, employer matches and plan fees are excluded.
  • Social Security, pensions, annuities and other income are excluded.
  • No withdrawals or loans are taken before retirement.

Sources

Common questions

How much do I need to retire?
Work backwards from the income you want rather than towards a round number. At a 4% withdrawal rate, every $1,000 a year of after-tax income needs about $25,000 of after-tax balance, so $40,000 a year needs roughly $1 million after tax, which is more before it. Adjust the withdrawal rate here and watch the income figure move.
Is 7% a reasonable return to assume?
It is a common long-run figure for a diversified equity portfolio before inflation, and it is a poor description of any particular decade. It is also before fees. If you want a real-terms answer, enter your expected return minus expected inflation, around 4%, and read the result as today’s dollars instead of future ones.
Are these figures adjusted for inflation?
No. Everything is nominal, in the dollars of your retirement year. At 3% inflation money loses about half its purchasing power over 24 years, so a balance projected forty years out buys far less than the number suggests. Entering a real return instead of a nominal one is the simplest way to get a figure in today’s money.
What is the 4% rule and should I trust it?
It is the finding that a retiree drawing 4% of their starting balance, adjusted for inflation, historically did not run out over thirty years in US markets. It is a useful way to size a target and a weak basis for a spending plan: it assumes a particular asset mix, a particular market history and a fixed horizon. Lower rates are more conservative; the calculator lets you set your own. To work backwards from a target balance instead, use the savings goal calculator.
Why does starting early matter so much?
Because most of the final balance is growth rather than contributions, and growth needs time more than it needs money. Set your current age forward five years and watch the balance fall by far more than five years of contributions, the missing amount is everything those early contributions would have earned. The compound interest calculator shows that mechanism on its own.
Should I count my employer match here?
Yes, include it in the monthly contribution figure, since it lands in the account the same way your own money does. Whether to prioritise the match over paying down debt is a separate question, and taking the match against paying off debt answers it.
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