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RetirementPlanCalc · US planning tools

Retirement Contribution Calculator

Estimate the fixed monthly contribution needed to reach a chosen future-dollar portfolio target.

Free · No account required · Results below

Your planning inputs

How to use the retirement contribution calculator

  1. Enter your own balances, time period, and spending or contribution amounts. Keep today’s dollars and future dollars separate.
  2. Choose return and inflation assumptions. Returns should reflect fees. The default numbers are examples, not recommendations or forecasts.
  3. Select Calculate. Results appear below your inputs. Read the assumptions alongside the estimate.
  4. Try lower returns, higher inflation, and a longer retirement horizon where the tool allows it. Save your assumptions so you can compare scenarios.

How the calculation works

Grow the starting balance to the target date. Divide the remaining target gap by the monthly annuity accumulation factor. At zero return, divide the gap by months. Floor new contributions at zero.

A simple example

With zero return, a $1,000,000 target, $100,000 starting balance, and 25 years, the required contribution is $3,000 a month.

Read the result with care

A calculator can make a planning tradeoff easier to see. It cannot predict future investment returns, personal spending, tax rules, or how long you will need your money.

These projections use simplified assumptions. Account limits, tax treatment, investment risk, healthcare costs, and the timing of Social Security can change a real retirement plan. Check account and benefit details with their official providers.

If a result looks too optimistic, compare several scenarios and review the inputs. A model that works with constant returns can still fail when actual returns vary during withdrawals.

Frequently asked questions

Are the default return and inflation rates forecasts?

No. They are editable assumptions for examples. No live market, inflation, or account data is loaded.

Does this calculator include taxes or account limits?

No. Review taxes, eligibility, account-access rules, and contribution limits separately. The employer-match tool is also a simplified one-tier formula.

Why do today’s dollars and future dollars differ?

Inflation changes purchasing power. Future-dollar results describe the modeled account or expense amount at a later date. Today-dollar results discount that amount using your inflation assumption.

Are my entries sent to an account service?

This calculator runs in your browser and does not connect to your bank, employer, or investment accounts. Avoid entering account numbers or other sensitive details.

Educational estimates only. Results are not personalized financial, investment, tax, or legal advice and do not guarantee retirement income. Read the methodology and disclaimer.

Planning tools maintained by RetirementPlanCalc. Report a calculation issue.