Retirement Calculator

Project a future retirement balance using a simplified monthly-compounding model. Enter an age range, current savings, monthly contributions, and an expected annual return to estimate future value, contributions, and modeled growth.

For educational purposes only. This calculator provides general estimates and does not provide financial, trading, tax, or legal advice.

Runs locally in your browser. No account. No signups.

Retirement Projection

Helpful for comparing assumptions (time, contribution size, return rate). Estimates only.

Your age today (whole years).
The age when you want the projection to end.
Starting balance used by the model.
Modeled as a consistent monthly deposit.
Converted to a monthly rate (simplified as annual return ÷ 12) in this model.
This tool does not adjust outputs for inflation.
Educational estimates only. This retirement calculator performs long-term projections based on user-entered values and simplified assumptions (such as contribution consistency, growth rates, and time horizon). It does not provide personalized financial, investment, tax, or legal advice, and it does not account for market volatility, sequence-of-returns risk, inflation variability, changing contribution limits, fees, employer plan rules, or individual tax circumstances. Results are illustrative scenarios — not predictions or guarantees. Calculations run locally in your browser. Verify assumptions independently before making decisions. See Disclaimer, Privacy Policy, and Terms of Use.

Methodology & Limits

  • Compounding model: constant annual return converted to a monthly rate (simplified as annual return ÷ 12).
  • Contributions: modeled as the same monthly deposit for the full period.
  • Output meaning: shows estimated future value, total contributions, and modeled growth.
  • What’s excluded: fees, taxes, inflation, contribution increases, and year-to-year return variability.

How Retirement Projections Work

A retirement projection is a math model that combines three ingredients: your starting balance, your ongoing contributions, and an assumed rate of return. This calculator applies a constant return assumption and estimates how compounding can accumulate over time.

What matters most in the model

  • Time: more months gives compounding more opportunities to build.
  • Contribution size: steady deposits can dominate outcomes over long periods.
  • Return assumption: small differences compound into large differences over decades.
Best use: change one variable at a time (return, contribution, retirement age) and compare outputs.
Reality check: real returns vary, and real accounts may have taxes and fees that change results.
Contribution timing: this model treats contributions as a consistent monthly deposit and compounds monthly. Different timing conventions (beginning vs end of month) can change results slightly. Use the tool for comparisons and sensitivity testing.

Common Inputs and Ranges

People often get stuck on the “right” assumptions. There usually isn’t a single right number—there are trade-offs. The goal is to understand how sensitive the projection is to each input.

Expected annual return

The “expected return” is a simplified placeholder for uncertain future performance. Real markets don’t deliver the same return every year, and accounts can have fees and taxes. This calculator uses a constant return to keep the model understandable and comparable.

Monthly contribution

In long time horizons, steady contributions can matter as much as (or more than) the return assumption. That’s why this calculator is most useful when you run multiple scenarios with different contribution levels.

Starting savings

Your starting balance matters because it compounds for the entire time period. Even small differences early can widen over decades in the model.

Tip: if your return assumption is high, run a lower-return scenario too. Projections can look “certain” even when outcomes are uncertain.
Tip: if your contribution is inconsistent, try an “average month” estimate and use it for comparison across time horizons.

Inflation and “Today’s Dollars”

This calculator shows nominal dollars (future dollars not adjusted for inflation). Inflation can reduce the purchasing power of money over time, which is why many people also think about results in “today’s dollars.”

This tool does not adjust for inflation because inflation assumptions vary and can be misunderstood. A simple way to sanity-check projections is to compare multiple return assumptions and remember that purchasing power may be lower than the nominal number suggests.

What this means: a large nominal number in the future may buy less than it would today. Use the tool for comparisons, not certainty.

Sensitivity Examples

The table below is illustrative only. It shows how a small change in assumptions can produce very different outputs. Use it as a reminder to test multiple scenarios.

Scenario (illustrative) Current age Retire age Starting savings Monthly contrib Annual return
Lower assumption 30 65 $25,000 $300 5%
Middle assumption 30 65 $25,000 $300 7%
Higher assumption 30 65 $25,000 $300 9%

Use the calculator above to compute the results for these examples (or your own). The purpose is to understand sensitivity, not to pick a “correct” return.

Mistakes to Avoid When Reading Projections

  • Treating a projection as a promise: it’s a model output, not a guarantee.
  • Ignoring fees/taxes: real-world frictions can reduce growth versus a simplified model.
  • Using one scenario only: run multiple assumptions to see how sensitive the outcome is.
  • Confusing nominal dollars with purchasing power: inflation can change what a future balance can buy.
Best use: compare scenarios. For example: change retirement age by 2–5 years, or adjust monthly contribution, and observe how the model responds.

Related Resources

Helpful next reads and tools for learning and scenario comparison.

Retirement Calculator FAQ

Does this calculator store or send my information?

No. The calculator runs locally in your browser. Inputs are not transmitted to FinFormulas and are not stored for signups.

Is this projection exact?

No. Results are estimates based on your inputs and simplified assumptions. Real outcomes vary with returns, fees, taxes, inflation, and contribution timing.

Does this include inflation?

No. Outputs are shown in nominal dollars and are not adjusted for inflation.

Will this tell me what I should do?

No. This tool provides arithmetic outputs from your inputs so you can compare scenarios. It does not provide individualized guidance or recommendations.

Reviewed & Updated

Calculator logic and on-page content reviewed for clarity and educational accuracy. Last review: December 2025.