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Retirement Calculator

Estimate retirement savings needed based on current age, income, savings rate, expected returns, and desired retirement lifestyle.

Tested tool guide Tested browser tools Checked August 16, 2026

What Retirement Calculator does, with a checked example

This tool starts from the retirement you describe and works backward: it turns the annual income you want into a required nest egg, then projects whether the money you save now, at the return you expect, reaches that figure by retirement age. Inputs are current age, income, savings rate, expected return, and desired retirement lifestyle. The number that surprises people most is the target itself: at the standard 4% withdrawal assumption, funding $60,000 a year means saving for a $1.5 million portfolio, before taxes.

Worked example

A concrete input and expected output from the current implementation.

Input

Age 30, income $80,000, saving $1,000/month (15%), planning to retire at 65, expecting 6% real return, wanting $60,000/year in retirement income.

Expected output

Required nest egg at 65: $1,500,000 (4% withdrawal rate). Projected balance: about $1,425,000. Shortfall: about $75,000, roughly 5% of the target, so the plan funds about 95% of the desired income. Closing the gap takes about $1,053/month instead of $1,000, or a target lifestyle of about $57,000/year instead of $60,000.

At a 4% withdrawal rate, $60,000 a year implies a $1.5 million target ($60,000 / 0.04). Saving $1,000 monthly for 420 months at 0.5% per month grows to $1,000 x ((1.005^420 - 1) / 0.005), about $1,425,000, leaving the roughly 5% gap.

How the result is produced

1

Lifestyle becomes a lump-sum target

Desired retirement income is converted into a required portfolio using an assumed withdrawal rate, most commonly 4% of the starting balance each year, adjusted for inflation afterward. That makes the target 25 times desired annual income: $60,000 a year needs $1.5 million. The withdrawal rate is the most sensitive assumption - at 5% the target falls to 20 times income, at 3.5% it rises to nearly 29 times.

2

Savings project to a balance

The calculator grows current savings from today's age to retirement, compounding monthly at the expected return, and compares the projected balance with the target. A shortfall is converted into the extra monthly amount needed - the payment that closes the gap. For a target stated in today's dollars, the expected return must be real, after inflation; a nominal return silently overstates the projection by the inflation rate.

Good uses

  • A 30-year-old earning $80,000 wants to know whether saving 15% of pay reaches retirement at 65 at the same standard of living, and how much to add if it does not.
  • A 45-year-old with a modest balance so far checks what a later start demands - the required monthly saving is far larger than at 30 because compounding has half as long to work.
  • After a raise, a worker asks how much of the increase to divert to savings: raising the savings-rate input shows the effect on the projected balance and the remaining shortfall.

Limits and checks

  • The 4% withdrawal assumption is a historical planning rule, not a guarantee. It is based on past U.S. stock-bond portfolios, and an unlucky sequence of returns early in retirement can exhaust the portfolio even when the average return matches the assumption.
  • The result is only as honest as the return you enter. Mixing today's-dollar goals with nominal stock-market returns (8-9%) inflates the projection by the inflation rate; for a today's-dollar target, use real, after-inflation returns.
  • Taxes, Social Security, and pensions are usually simplified or ignored. Pre-tax 401(k) money differs from post-tax Roth dollars, and any pension or Social Security income reduces how much must come from savings - so the requirement shown is typically an upper bound, not the final number.

Common questions

Why does the tool say I need such a huge number - 25 times my annual income?

At a 4% withdrawal rate the target is 25 times the income you want, and it must fund a retirement that can last 30 years and keep pace with inflation. $60,000 a year means $1.5 million before taxes. The figure shrinks once Social Security, a pension, or part-time work is counted, because less of the income has to come from savings.

Can I trust the return assumption I enter?

Only as a long-range planning guess. The calculator applies one constant rate to every year, but real portfolios swing, and the order of good and bad years matters for how long money lasts. Run the tool at a lower return as well: if a one-point change in the assumption swings the answer a lot, plan toward the conservative side.

References and verification

The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.

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