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Retirement Calculator.
Two numbers that matter: what you'll have, and what the life you want will cost in the dollars of that year. This shows both, and the monthly amount that closes any gap.
Estimates for planning only. Your lender, dealer or tax authority sets the real numbers, and rates, fees and rules change. This is not financial, tax or legal advice. Nothing you type here leaves your browser. Terms.
Your balance by age
Growing while you save, then drawing down in retirement.
Guide
How to use the Retirement Calculator
- Enter your Current age and Retirement age. The gap is how many years your money has to grow.
- Set Years in retirement, how long the savings must last. Guess long; outliving your money is the worse mistake.
- Enter Current retirement savings across all accounts, and your Monthly contribution including any employer match.
- Set Yearly increase in contributions. If you save more as your pay rises, 2% or 3% is a reasonable guess; enter 0 for a flat contribution.
- Enter Return before retirement and Return during retirement. Many people use a lower second number because they shift toward safer holdings once the paychecks stop.
- Enter Inflation. It converts your income goal from today's dollars into the dollars you will actually spend.
- Enter the Monthly income you want in retirement, then Other monthly income in retirement such as Social Security or a pension. Both are in today's dollars, and only the difference needs funding.
- Compare the Projected savings at retirement headline with the Nest egg needed line. The Surplus or Shortfall line, Extra monthly saving to close it, Savings last until age and the Your balance by age chart tell you whether the plan holds.
How the math works
The calculator runs two projections and compares them. The first is what you will have: your savings grow at the pre-retirement return, the contribution is added every month, and it rises once a year by the yearly increase. The second is what you will need: the income gap in today's dollars (what you want minus what Social Security or a pension covers) is inflated to the year you retire, then keeps rising with inflation.
The nest egg you need is not the first-year gap times the number of years. Money you have not withdrawn yet keeps earning the retirement return, so the calculator discounts every future withdrawal back to your retirement date and adds them up. That total is the balance that hits zero exactly when your years in retirement end.
If you fall short, the calculator asks how much more per month, starting now and growing at the same yearly increase, would close the gap. That is the Extra monthly saving to close it figure.
The formula
Growth: each month Balance = Balance × g1 + C, where g1 = (1 + R1)^(1 ÷ 12); once a year C = C × (1 + i).
First-year monthly need N = (W − O) × (1 + f)^Y
Nest egg needed = sum over every retirement month m of N_m ÷ g2^m, where g2 = (1 + R2)^(1 ÷ 12) and N_m rises by (1 + f) each retirement year.
R1 and R2 are the returns before and during retirement, C the monthly contribution, i the yearly increase, W the income you want, O your other income, f inflation, Y the years until retirement. Surplus or shortfall = projected savings − nest egg needed.
Worked example
You are 35, retiring at 65, and want the money to last 25 years, to age 90. You have $50,000 saved and put in $800 a month, rising 2% a year. You expect 7% before retirement and 5% during it, with 2.5% inflation. You want $5,000 a month in today's dollars, with $1,800 of it from Social Security.
What you will have. The monthly growth factor at 7% is 1.07^(1 ÷ 12) = 1.005654. Your $800 becomes $816 in year two and about $1,420.68 in year 30; in all you contribute about $389,454.
| Age | Projected balance |
|---|---|
| 35 | $50,000 |
| 45 | $246,556 |
| 55 | $665,666 |
| 60 | $1,021,484 |
| 65 | $1,529,681 |
Of the $1,529,681, about $1,090,228 is growth; your deposits plus the starting $50,000 are the smaller share.
What you will need. The gap today is 5,000 − 1,800 = $3,200 a month. Thirty years of 2.5% inflation multiplies prices by 1.025^30 = 2.0976, so the first-year need is 3,200 × 2.0976 = $6,712 a month, reaching about $12,141 in the final year. Discount all 300 withdrawals back to age 65 at 5% and the nest egg needed is $1,497,167.
The verdict. 1,529,681 − 1,497,167 is a surplus of about $32,514. The plan is on track and the money does not run out within 25 years. The chart shows the balance falling slowly at first ($1,093,676 at 80), then fast ($110,105 at 90), because every withdrawal is bigger than the last.
What moves the result most
A $32,514 surplus on a $1.5 million plan is a rounding error; nudge one input and it flips. Each line below changes only the thing named.
- Return before retirement drops to 6%. Savings at 65 fall to $1,256,565, a shortfall of about $240,602; the fix is an extra $198.56 a month starting now.
- Inflation runs 3% instead of 2.5%. Savings are unchanged but the nest egg needed jumps to $1,826,679, a shortfall of about $296,998. Money runs out at 86.
- Skip the 2% yearly increase. A flat $800 forever gets you $1,316,175 at 65 and the money runs out at 87. The raises are worth about $213,500.
- Retire at 62 instead of 65. You arrive with $1,203,458 against a $1,390,268 need, a shortfall of about $186,811 (still funding 25 years, so now only to age 87). Retire at 67 and the surplus grows to about $215,866.
- Start the same plan at 45 instead of 35. You reach 65 with $665,666 against a need of $1,169,584, and closing the gap takes an extra $853.77 a month. Ten lost years roughly doubles the savings rate you need.
- Live to 95 instead of 90. The need rises to $1,702,772 and the surplus becomes a $173,091 shortfall.
How to read the result without fooling yourself
Treat Projected savings at retirement as the midpoint of a wide range, not a promise. The return you type in is applied every month for 30 years; real markets deliver that average with a lot of noise. Run it a point or two lower and make sure you can live with that answer.
The headline is in future dollars. $1,529,681 at 65 buys what about $729,264 buys today, which is why the inflation setting matters so much.
The Compound Interest Calculator shows the growth side on its own; the ROI Calculator turns an account's past performance into an annualized return you can try in the Return before retirement field.
What this calculator doesn't do
It does not model taxes, which depend on whether your accounts are pre-tax, Roth or taxable. It does not handle sequence-of-returns risk, where a bad market in your first retirement years does far more damage than the same bad year later. It assumes steady returns, steady inflation, contributions that never pause and other income that keeps pace with inflation.
Results are estimates. Your plan statements, the Social Security Administration's benefit estimate and your tax authority's figures govern.
Frequently asked questions
How much do I need to retire?
Enough that your savings, growing at your retirement return, can cover the gap between the income you want and what Social Security or a pension pays, for as many years as you expect to live. In the example, a $3,200-a-month gap in today's dollars over 25 years from age 65 needs about $1,497,167 at retirement.
Is $800 a month enough to retire on?
Starting at 35 with $50,000 saved, $800 a month rising 2% a year at a 7% return grows to about $1,529,681 by 65. Whether that is enough depends on your income goal and other income; in the example it is just enough, with a surplus of about $32,514.
What return should I assume before retirement?
Use something you would be comfortable being wrong about. Dropping the example from 7% to 6% turns a small surplus into a $240,602 shortfall, so run the calculator at a lower rate than you hope for and make sure that answer still works.
Why is my first-year retirement income so much higher than what I entered?
Because the calculator inflates today's dollars to the year you retire. At 2.5% inflation, prices roughly double over 30 years (a factor of 2.0976), so a $3,200 monthly gap today becomes about $6,712 a month at 65.
How much does waiting to start saving cost?
A lot. Running the example plan from age 45 instead of 35 with the same $50,000 and $800 a month ends at $665,666 instead of $1,529,681, and closing the gap takes an extra $853.77 a month, more than doubling the savings rate.
Does retiring a few years later make a big difference?
Yes, because you add contributions and growth while shortening the years you draw down. Retiring at 67 instead of 65 in the example raises the surplus from about $32,514 to about $215,866; retiring at 62 creates a shortfall of about $186,811.
Does this calculator account for taxes or Social Security changes?
No. It assumes the other income you enter keeps pace with inflation, and it ignores taxes entirely, so a plan built on pre-tax accounts will support less spending than the headline suggests. Use it for direction, then confirm with your plan statements and the Social Security Administration's benefit estimate.
Estimates for planning only. Your lender, dealer or tax authority sets the real numbers, and rates, fees and rules change. This is not financial, tax or legal advice. Nothing you type here leaves your browser. See the terms of use.
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