Retirement Planning Calculator

Free online retirement calculator. Enter age, retirement age, savings, monthly contributions, expected return and inflation to see nominal wealth, purchasing power and gap to your target.

See exactly how far you still are. Plug in your current savings, monthly contributions, expected return and inflation to reveal your nominal balance at retirement, real purchasing power and gap to target.

Nominal Wealth at Retirement
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Purchasing Power (Today)
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Gap vs Target
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Retirement Planning 101

Why Plan for Retirement

Longer life expectancy, lower public-pension replacement rates and persistent inflation make relying on state benefits alone risky. Starting early lets compounding turn every dollar you save today into several dollars decades later.

The Key Variables

Variable Meaning Intuition
Age / Retirement Age Horizon = retirement − current Longer is better for compounding
Current Savings Starting balance Higher start, higher terminal value
Monthly Contribution Ongoing input Drives the pace of accumulation
Expected Return Compounded portfolio return Typically 5–9% for balanced portfolios
Inflation Purchasing-power erosion 2–4% long-run average
Retirement Target In today's money Roughly 25× annual expenses

How We Model It

We compound monthly and iterate year by year:

For each year y = 0..years_to_retirement:
  nominal[y] = balance
  real[y]    = nominal[y] / (1 + inflation)^y
  End-of-year: repeat 12 times: balance = balance × (1 + monthly_r) + monthly_contribution

4% Rule and Target Size

The Trinity Study suggests that with a 7% return / 3% inflation portfolio, withdrawing 4% of initial capital yearly has a very high 30-year success rate. Hence Target ≈ 25 × annual spending.

How to Improve Real Wealth at Retirement

  1. Raise the savings rate—the only variable fully in your control.
  2. Optimise allocation—an appropriate equity/bond mix lifts long-run returns.
  3. Diversify against inflation—add real assets, REITs and inflation-linked bonds.
  4. Delay retirement—two extra working years both add savings and shorten drawdown.

Caveats

  • We ignore sequence-of-return risk.
  • Taxes, Social Security and healthcare are not modelled explicitly.
  • Enter an after-tax, after-fee expected return for realistic output.

Open-Source License: This tool uses finance.js by Essam Al Joubori (MIT) and Chart.js by Chart.js contributors (MIT). Both are bundled locally in accordance with their license terms.

Frequently Asked Questions

How much do I need to retire?
A common rule of thumb is 25× your annual retirement spending, matching a 4% safe withdrawal rate. Add a buffer for emergencies and healthcare.
How is real purchasing power computed?
We divide nominal wealth at retirement by (1 + inflation)^years, converting future dollars into today's equivalent.
Why focus on monthly contributions rather than higher returns?
Higher returns come with higher risk and are not fully in your control. Contributions are 100% controllable and compound massively over decades.
What is a reasonable inflation assumption?
Developed economies average 2–3% over the long run; emerging markets 3–5%. You can also use your country's 20-year CPI average.
Is early retirement (FIRE) realistic for me?
With a savings rate above 50%, FIRE becomes feasible. At 25% you need ~32 years to reach 25× spending; at 50% around 17 years; at 75% just about 7.
Does this tool include Social Security or pensions?
No. Estimate the monthly benefit and treat it as reduced future spending, which lowers the nest egg you must build yourself.
What if real returns turn negative?
That is sequence-of-return risk. Regular contributions smooth entry cost, and a glide-path allocation (lower equity as you age) reduces the impact.