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Retirement Contribution Calculator

Work backward from a retirement target to the monthly amount you may need to save, and compare it with what you contribute today.

Free No signup Runs in your browser

Your Details

Optional. Used to show your contribution gap.

Your calculations are performed locally in your browser. Nothing you enter is sent or stored.

Your Results Estimate

Required Monthly Contribution —
Required Annual Contribution
—
Target in Future Dollars
—
Projected Balance (current contribution)
—
Monthly Contribution Gap
—
Required vs. current savings path

Results are estimates based on the assumptions you entered. Actual results will vary and are not guaranteed.

About the Retirement Contribution Calculator

A target in today's dollars is converted into future dollars using your inflation assumption, so the goal keeps the same purchasing power by the time you retire.

The difference between the required contribution and your current contribution is your contribution gap — a practical number to plan around.

How It Works

First the calculator inflates your target to retirement-age dollars. Then it projects your current savings forward and solves for the level monthly contribution that closes the remaining gap at your expected return.

It also projects your balance if you keep contributing your current monthly amount, so you can see the shortfall or surplus.

Formula

Target in future dollars
Targetfuture = Targettoday × (1 + inflation)years
Required monthly contribution
PMT = [Targetfuture − S(1 + i)n] × i / [(1 + i)n − 1]
Contribution gap
Gap = Required PMT − Current monthly contribution

Example

A 35-year-old with $50,000 saved wants the equivalent of $1,000,000 in today's dollars at 65, assumes a 7% return and 3% inflation, and saves $500 a month today.

Inputs

Target (today's $)
$1,000,000
Years
30
Return / inflation
7% / 3%

Results

Target in future dollars
$2,427,262.47
Required monthly
$1,750.09
Monthly gap
$1,250.09

Assumptions & Limitations

  • Constant return and inflation every year.
  • Level monthly contributions made at the end of each month; no increases over time.
  • Not included: employer matches, taxes, fees, IRS contribution limits, Social Security, and pensions.

Understanding Your Results

  • Required Monthly Contribution: The amount to save each month to reach the inflation-adjusted target.
  • Monthly Contribution Gap: How much more per month you would need beyond your current contribution.
  • Projected Balance: Where your current savings plan is projected to land.

Frequently Asked Questions

How much do I need to retire?
It depends on your expected spending, other income such as Social Security, and how long retirement may last. Many people estimate annual spending and divide by a sustainable withdrawal rate to set a target.
Why adjust the target for inflation?
A dollar in 30 years typically buys less than a dollar today. Inflating the target keeps it equal to your goal in today's purchasing power.
What if my required contribution is too high?
Common levers are saving longer, retiring later, adjusting the target, or increasing contributions over time. You can test each by changing the inputs.
Does this include my employer match?
Only if you include it in your current monthly contribution. The 401(k) Calculator models matching in detail.
Is the result guaranteed?
No. It is an estimate based on constant assumptions; actual returns and inflation will differ.