Retirement Calculator
Enter your age, savings, and monthly contributions to instantly see your projected nest egg, how much comes from growth versus contributions, whether you hit your target, and how many years the pot could last. No sign-up — your numbers never leave your browser.
What is the Retirement Calculator?
The Retirement Calculator turns five simple inputs — your current age, planned retirement age, what you have saved today, how much you add each month, and the return you expect — into a clear picture of your future. Instead of a single mysterious number, it shows your projected nest egg at retirement, how much of it came from your own contributions versus investment growth, whether you reach a target you set, and roughly how many years the money could last once you stop working.
How to use it
- Enter your current age and your planned retirement age.
- Enter your current savings — everything already invested for retirement today.
- Enter your monthly contribution — what you add every month from now until you retire.
- Enter your expected annual return (for example, 7 percent for a diversified portfolio).
- Optionally add an inflation rate to see the result in today's money, a target amount to check if you are on track, and annual retirement spending to estimate how long the pot lasts.
Results update the instant you change a value — there is no Calculate button to wait on and nothing to submit, so you can try different ages and contributions in seconds and close the tab when you are done.
The formula behind it
The calculator compounds your balance month by month. Each month it adds your contribution, then grows the whole balance by the monthly return, which is your annual return divided by twelve:
balance = (balance + monthly) x (1 + annualReturn / 12)
Repeating this for every month until retirement produces the final nest egg.
Investment growth is simply the final balance minus your starting savings and
minus everything you contributed. When you supply an inflation rate, the
final balance is divided by (1 + inflation)^years to express it
in today's purchasing power. The years-the-pot-lasts figure withdraws your
annual spending each year while the remaining balance keeps earning the
return, counting the years until the money is gone.
Examples
- Starting young: Age 30 retiring at 65, with $20,000 saved and $500 a month at 7%, projects to about $1,135,903. Of that, $210,000 came from contributions and roughly $905,903 from compound growth.
- Catching up with inflation: Age 40 retiring at 67, with $50,000 saved and $800 a month at 6%, projects to about $900,100 nominal — but after 2.5% inflation that is closer to $462,111 in today's money.
- How long it lasts: A $800,000 pot spending $50,000 a year at a 4% return lasts about 24 years before it is exhausted.
Common use cases
- Checking whether your current savings rate is enough, or whether you need to contribute more.
- Comparing an earlier versus a later retirement age to see the cost of stopping work sooner.
- Seeing how a one or two percentage point change in expected return reshapes the outcome.
- Translating a far-off nominal balance into today's money so the goal feels real.
- Estimating how many years your nest egg can support your planned spending.
Why use this one
Most retirement calculators stop at a single end balance or hide the details behind a sign-up. This one shows the full picture on one screen: the compound projection, the split between contributions and growth, an on-track check against your target, an inflation-adjusted figure in today's money, and an estimate of how many years the pot can fund your spending. It is instant (results update as you type) and private: every figure is computed in your browser and nothing is ever uploaded, stored, or shared. No account, no email, no app.
Results are estimates for general informational and educational purposes only and are not financial, tax, or investment advice. Real returns vary, and taxes and fees are not modeled. Always confirm important decisions with a qualified professional.
Frequently asked questions
How does this retirement calculator work?
It compounds your starting savings plus your monthly contributions month by month at your expected annual return, until your planned retirement age. The result is your projected nest egg, how much came from contributions versus investment growth, and an optional inflation-adjusted figure in today's money.
What return rate should I use?
There is no single correct number, but many planners use a long-run average of around 6 to 8 percent for a diversified stock-heavy portfolio before inflation, or roughly 4 to 5 percent after inflation. Use a conservative figure if you want a safer estimate, and try a few values to see the range of outcomes.
What does the inflation option do?
Inflation quietly erodes what your money can buy. When you enter an expected inflation rate, the calculator also shows your final balance in today's purchasing power, so a million dollars decades from now is translated into what it would actually feel like to spend now.
How is the years-the-pot-lasts estimate calculated?
If you enter an annual retirement spending amount, the tool withdraws that sum each year from your projected balance while the remainder keeps earning your return, and counts how many years pass before the money runs out. If the balance grows faster than you spend it, it reports 60 or more years as effectively self-sustaining.
Is my financial information saved or sent anywhere?
No. Every calculation runs entirely in your browser. The ages, savings, contributions, and spending figures you type are never uploaded, stored, or shared. Close the tab and they are gone.